11. The following code snippets have security flaws. Which of the choices below can be used as id to achieve the SQL Injection attack?
(A)
(B)
(C)
(D)
(E)

7. Assume there are four frames in main memory. Consider the following page reference string: 2, 1, 6, 4, 1, 2, 5, 3, 1, 2, 1, 6, 7, 3, 6, 1, 2, 1, 6, 3. How many page faults occur for the OPT (Optimal Page-replacement Algorithm) replacement? Notes: All frames are initially empty, so the first unique pages will all cost one fault. (A) 7 (B) 8 (C) 9 (D) 10 (E) 11

8. Consider the execution of the following set of processes on a single-core processor.Assume we use preemptive SJF (Shortest-Job-First) scheduling. What is the average waiting time? (A) 10 (B) 12 (C) 14 (D) 16 (E) 18

9. Suppose computers A and B have IP addresses 10.105.1.113 and 10.105.1.91, respectively, and they both use the same netmask N. Which of the values of N given below should be used if A and B belong to the same network? (A) 255.255.255.255 (B) 255.255.255.250 (C) 255.255.255.240 (D) 255.255.255.224 (E) 255.255.255.192

10. Assume a network device sends out data at the rate of 4,000 bps. How long does it cost to send a file of 100,000 characters? (A) 100 seconds (B) 200 seconds (C) 300 seconds (D) 400 seconds (E) 50 seconds

12. Suppose we have two tables, named TABLE-A and TABLE-B, respectively, as shown below.  (A) The result is a table of 7 records. (B) There are 5 columns in the resulting table. (C) Green appears in three records of the resulting table. (D) Eight appears in two records of the resulting table. (E) JOIN cannot be performed for these two tables.

13. In a 3-level memory hierarchy system, the hit time for each level is T1 = 5 ns (L1-cache) T2 = 200 ns (L2-cache) T3 = 600 ns (Main memory) The local hit rate in each level is H1 = 0.9 (L1-cache), H2 = 0.8 (L2-cache), and H3 = 1 (It is assumed that we can always find the data in main memory). If the average access time (ns) of this memory is K. What is the value of “{Round(K*123)} mod 5” ? (A) 0 (B) 1 (C) 2 (D) 3 (E) 4

14. Let AB*CD-/E+ be an postfix expression. If A=6, B=3, C=4, D=5, and E=8. What is the result of this postfix expression after evaluation? (A) -10 (B) -8 (C) 8 (D) 9 (E) 10

15. Let the height of a tree be the number of nodes along the longest path from the root node to the leaf nodes. Consider the integers 30, 41, 25, 29, 94, 37, 70, 23, 65, 75 in the specified order to develop a binary search tree. Which of the following is TRUE? (A) The node for 37 is an internal node. (B) The root node is 41. (C) The node for 70 has only one child. (D) The height of the tree is 5. (E) The node for 75 is a child of the node for 94.

16. What will be the output of the following C code ?   (A) 2 (B) 3 (C) 4 (D) 5 (E) None of the above 

17. Consider the following instruction mix for a processor: ALU operations: 40%, uses 4 cycles. Branch operations: 30%, uses 4 cycles. Memory references: 30%, uses 5 cycles. The un-pipelined processor has a clock cycle time of 1 ns. The pipelined processor has a clock cycle time of 1.2 ns. Suppose that we ignore any latency and hazards, and assume that the pipelined processor has an ideal CPI (cycles per instruction) of 1. How much speedup can be achieved when comparing the un-pipelined processor and the pipelined processor? (A) 3.28 (B) 3.35 (C) 3.58 (D) 3.86 (E) 3.98