Explanation : Electromagnetic waves with frequencies not ranges from 300 GHz to 400 THz. It ranges from (0.3 to 300) GHz. So, I option is Incorrect. Propagation is line-of-sight.Correct Very high-frequency waves cannot penetrate walls.Correct Use of certain portions of the band requires permission from authorities.Correct So, option (A) is correct.
Explanation : Throughput is amount of data moved successfully from one place to another place. i.e. 12,000 frames per minute. Each Frame is carrying 10,000 bits So, 12,000 * 10,000 / 60 seconds. = 2 * 1000000 bits / seconds. = 2 Mbps. So, option (B) is correct.
POP3 is post office protocol Version 3.POP is a protocol which listens on port 110 and is responsible for accessing the mail service on a client machine. POP3 works in two modes such as Delete Mode and Keep Mode.
IMAP is Internet Messaged Access Protocol which is used by email server to maintain a central repository that can be accessed from any machine.