Expected Questions Series 6

1) A machine has a physical memory of 64 Mbyte and a virtual address space of 32 - bit. The page size is 4kbyte, What is the approximate size of the page table?
a. 24 Mbyte
b. 16 Mbyte
c. 2 Mbyte 
d. 8 Mbyte

2) We have a process that has been allocated 3 page frames and initially none of the pages of the process are available in the memory. The following sequence of page references (reference string) is made by the process : 

1, 2, 1, 3, 7, 4, 5, 6, 3, 1
If Optimal Page Replacement policy is used,  _______ page faults will occur for the above reference string.
a. 7
b. 8
c. 9
d. 6

3) Which of the following statements is not true for the deadlock prevention and deadlock avoidance schemes? 

a. Deadlock avoidance is less restrictive than deadlock prevention.
b. In deadlock prevention, the request for resources is always granted, if the resulting state is safe.
c. It is the priority to have the knowledge of resource requirements for deadlock avoidance. 
d. In deadlock avoidance, the request for resources is always granted, if the resulting state is safe. 

4) What does the Cryptographic hash function return when it takes an arbitrary block of data?

a. Variable size bit string
b. Fixed size bit string
c. All of the Above
d. None of the Above

5)  If ' h ' is a hashing function and it is used to hash ' n ' keys into a table of size ' m '  where n <= m . What is the expected number of collisions involving a particular key ' x ' ?

a. less than 1. 
b. less than n.
c. less than m. 
d. less than n / 2.

6) Which of the following is the depth of a Complete Binary Tree?

a. Dn = n log2n
b. Dn = n log2n + 1 
c. Dn = log2n
d. Dn = log2n + 1 

7)  In graphs, A hyperedge is an edge that is allowed to take on any number of _____________.

a. vertices
b. edges 
c. both a and b
d. labels

8) What is degree 0 isolation?

a. Transaction does not read dirty data from other transactions.
b. Transaction does not commit any writes until it completes all its writes.
c. Transactions do not dirty data read by a transaction before the transaction commits.
d. A transaction does not overwrite data updated by another user or process.

9) What is a degree of relation?

a. It is the number of attributes of its relation schema.
b. The number of relationships with other tables
c. Number of association among two or more entities
d. Number of foreign key dependencies

10) Which of the following is / are known as a minimal superkey?

a. Primary key
b. Foreign key
c. Unique key
d. Candidate key 

Answers:

1) c

2) a

3) d

4) b

5) a

6) d

7) a

8) d

9) a

10) d