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Consider a system where each file is associated with a 16-bit number. For each file, each user should have the read and write capability. How much memory is needed to store each user’s access data?

Consider a system where each file is associated with a 16-bit number. For each file, each user should have the read and write capability. How much memory is needed to store each user’s access data? Correct Answer 16 KB

Answer: Option 1

Explanation: 

The question says that each file is associated with a 16-bit number.

Hence the maximum number of files possible will be 216.

for each file, we have to maintain/store access data.

and each user can read or write capability 

we have only 4 possible access data for a particular user 

No Read, No Write

No Read, Write

Read, No Write

Read, Write 

For indicating 4 cases we need only 2 bits for each user.

Hence the total number of bits needed 2 × 216 ≡ 217 bits

Option 1: 16 KB

16 KB = 16 × 210 bytes = 16 × 210 × 8 bits = 217 bits.

Therefore option 1 is the correct answer:

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