- Diket:
berkas memuat
10.000 record
panjang record
20 byte
data dencity
1.600 Bpi
laju pita 100
inch/detik
IRG 0,25 inch
IBG 0,5 inch
Blocking factor
25
Ditanya:
a. -- Hitung dengan metode tanpa blocking, berapa record yang bias
dimuat untuk pita dengan panjang 100 inch?
-
Berapa waktu akses untuk pita
dengan panjang 100 inch?
b. - Hitung dengan metode blocking, berapa record yang bias dimuat
untuk pita dengan panjang 100 inch?
-
Berapa waktu akses untuk pita
dengan panjang 100 inch?
Jawab:
a)
100 = Jumlah Record*(panjang 1
record + IRG)
100 = (Jumlah
record)*((20 byte/1600bpi)+0.25 inch)
100 = (Jumlah
record)*(0.0125+0.25 inch)
100 = Jumlah
record*0.2625
Jumlah record =
100/0.2625
Jumlah record = 380.95 record
Lama Akses = Panjang
pita/laju
Lama
Akses=100/100
Lama Akses= 1 detik
b)
100 = (Jumlah block) * (panjang
setiap block)
100 = (Jumlah
record/ factor blocking)*(panjang 1 block + IBG)
100 = (Jumlah
record / 25) * ((25 * 20byte / 1600 Bpi)+0.5)
100 = (Jumlah
record / 25) * (0.3125+0.5)
100= (Jumlah
record / 25) * 0.8125
Jumlah record =
2500 / 0.8125
Jumlah record = 3076.92
Lama Akses =
Panjang pita/laju
Lama
Akses=100/100
Lama Akses= 1 detik
c) Diketahui data:
|
NIM (CHAR[10])
|
NAMA (CHAR[10])
|
|
121051025
|
Seprindo AP
|
|
141052012
|
Ari PA
|
Penggambaran
penyimpanan dalam pita magnetic 9 track, menggunakan kode ASCII 8 bit, dengan odd parity (ganjil) untuk metode tanpa
blocking sebagai berikut.
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1
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2
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1
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0
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5
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1
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0
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2
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5
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sp
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S
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e
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p
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r
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i
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n
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d
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o
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sp
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A
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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1
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1
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1
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1
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1
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1
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1
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1
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0
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1
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1
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1
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1
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1
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1
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1
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1
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1
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1
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1
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0
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1
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1
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1
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1
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1
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1
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1
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1
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0
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1
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1
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1
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1
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1
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1
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1
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1
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1
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0
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1
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0
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1
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1
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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1
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1
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0
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1
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0
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0
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0
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0
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0
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0
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1
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0
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0
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0
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1
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0
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0
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1
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1
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0
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0
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1
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1
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1
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0
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0
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0
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1
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0
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0
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0
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0
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0
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1
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0
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0
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1
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0
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0
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1
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0
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1
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0
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1
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0
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0
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1
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0
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1
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0
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1
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1
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0
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0
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1
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0
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1
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1
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0
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0
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1
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0
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0
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1
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0
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1
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0
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0
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0
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1
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1
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0
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1
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0
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1
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0
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1
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1
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0
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1
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1
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0
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0
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1
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0
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1
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1
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4
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1
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0
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5
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2
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0
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1
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2
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sp
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A
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r
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i
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sp
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P
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A
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sp
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sp
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sp
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sp
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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1
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1
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1
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0
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1
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1
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0
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0
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0
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0
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1
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1
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1
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1
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1
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1
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1
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1
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1
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1
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0
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1
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1
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1
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0
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0
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1
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1
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1
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1
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1
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1
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1
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1
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1
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1
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1
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1
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1
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0
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0
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1
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0
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0
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1
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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1
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0
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0
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0
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0
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0
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0
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0
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0
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1
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0
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0
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1
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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0
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1
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0
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0
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1
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0
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0
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1
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0
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0
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0
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0
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0
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0
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0
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0
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1
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0
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1
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0
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1
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0
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0
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1
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0
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0
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1
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0
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1
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0
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0
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1
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0
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0
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0
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0
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0
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0
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0
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1
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1
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0
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1
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0
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0
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0
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1
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1
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1
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0
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1
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1
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0
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0
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0
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0
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