41. With an IP address set starting with 150, you currently have six offices that you are treating as subnets. Plans are in place to open 10 more offices before the end of the year. What subnet mask should you use to satisfy the needed number of subnets and maximize the number of hosts available at each site?

A. 192
B. 224
C. 240
D. 248
E. 252

42. A machine that connects to two or more electronic mail systems and transfers mail messages among them is known as

A. Gateways
B. mail gateway
C. bridges
D. User Agent
E. None of the above

43. If digital data rate of 9600 bps is encoded using 8-level phase shift keying (PSK) method, the modulation rate is

A. 1200 bands
B. 3200 bands
C. 4800 bands
D. 9600 bands
E. None of the above

44. Error detection at a data link level is achieved by

A. bit stuffing
B. cyclic redundancy codes
C. Hamming codes
D. equalization

45. When the computer provides the manager with a multiple choice of possible answers, the prompting technique is

A. question and answer
B. form filling
C. open-ended question
D. menu selection
E. None of the above