18. Assume a system bas a TLB hit ratio of 90%. It requires 15 nanoseconds to access the TLB, and 85 nanoseconds to access main memory. What is the effective memory access time in nanoseconds for this system?
(A)108.5
(B) 100
(C)22
(D)176.5
(E) 32 

複選題14. Choose the correct statements from the multiple choices (A)Each container includes the application, the necessary binaries and libraries and an entire guest operating system (B) Containers running on a single machine all share the same operating system kernel (C)Virtual machine run as an isolated process in user space on the host operating system (D)Containers are lightweight than virtual machines (E) None of the above

複選題15. Choose the correct statements from the multiple choices (A)It is not allowed for routers to fragment IPv6 packets. (B) DHCP allows a host to dynamically obtain its IP address from network server when it joins the network. (C)NAT is used to translate IP addresses to hardware addresses. (D)DNS is used to find the hardware address of a local device (E) None of the above

16. When communicating with sockets, a client process initiates a request for a connection and is assigned a port by the host computer. Which of the following would be a valid port assignment for the host computer?(A)21 (B) 23 (C)80 (D)1625 (E) None of the above

17._______is/are not a technique/s for handling critical sections in operating systems. (A)Nonpreemptive kernels (B) Preemptive kernels (C)Spinlocks (D)Peterson's solution (E) Dekker's algorithm

19. Given the reference string of page accesses: 1 2 3 4 2 3 4 1 2 1 1 3 1 4 and a system with three page frames, what is the final configuration of the three frames after the LRU algorithm is applied? Assume the FIFO queue is left out right in. (A)1,3,4 (B) 3, 1.4 (C)4,1,2 (D)1,2,3 (E) 1,4,3

20. Which of the following is true of a blocking system call? (A) The application continues to execute its code when the call is issued. (B) The call returns immediately without waiting for the I/O to complete.(C) The execution of the application is suspended when the call is issued. (D)Blocking application code is harder to understand than nonblocking application code (E) None of the above

26.Deficiency in vitamin C leads to which disease? (A) Ostemalacia； (B) Scurvy； (C) Beriberi； (D) Megaloblastic anemia.

27. Which organ stores the most vitamin A? (A) Kidney； (B) Liver； (C) Brain； (D) Bone.

28. Who may have lower serum vitamin D level? (A) Elderly； (B) Dark skin (black) people； (C) Obese individuals； (D) All of the above.

29. Which of the following nutrients provides the highest amount of energy per gram? (A) Protein； (B) Carbohydrates； (C) Fat； (D) Alcohol.