PGT Computer Science (Level-3), (HTET Practice MCQs) (Part-IV)

Total Questions: 100

71. Which of the following services is not provided by wireless access point in 802.11 WLAN?

Correct Answer: C. Error correction

72. Which of the following fields in IPv 4 datagram is not related to fragmentation?

Correct Answer: A. Type of service

73. Four channels are multiplexed using TDM. If each channel sends 100 bytes/second and we multiplex 1 byte per channel, then the bit rate for the link is .................... .

Correct Answer: D. 3200 bps

74. In a typical mobile phone system with hexagonal cells, it is forbidden to reuse a frequency band in adjacent cells. If 840 frequencies are available, how many can be used in a given cell?

Correct Answer: A. 280

75. Which of the following algorithms is not used for line clipping?

Correct Answer: B. Sutherland-Hodgeman algorithm

76. A virtual memory has a page size of 1K words. There are eight pages and four blocks. The associative memory page table contains the following entries:

Which of the following list of virtual addresses (in
decimal) will not cause any page fault if referenced by
the CPU?

Correct Answer: C. 1020, 3012, 6120, 8100

77. Suppose that the number of instructions executed between page fault is directly proportional to the number of page frames allocated to a program. If the available memory is doubled, the mean interval between page faults is also doubled. Further, consider that a normal instruction takes one microsecond, but if a page fault occurs, it takes 2001 microseconds. If a program takes 60 sec to run, during which time it gets 15,000 page faults, how long would it take to run if twice as much memory were available?

Correct Answer: C. 45 sec

78. Consider a disk with 16384 bytes per track having a rotation time of 16 msec and average seek time of 40 msec. What is the time in msec to read a block of 1024 bytes from this disk?

Correct Answer: B. 49 msec

79. Consider the following statements:

(a) Windows Azure is a cloud-based operating system.
(b) Google App Engine is an integrated set of online services for consumers to communicate and share with others.
(c) Amazon Cloud Front is a web service for content delivery.
Which of the statements is (are) correct?

Correct Answer: B. Only (a) and (c)

80. In Unix, the login prompt can be changed by changing the contents of the file ................... .

Correct Answer: C. gettydefs