21) Which device is used to amplify or regenerate digital signals received while sending them from one port of a network into another?

22) Which device modulates analog signal to encode digital information and demodulates carrier signal to decode the transmitted information over the telephone network?

23) Which device is used to connect one network with another network that uses different protocols?

24) Which device forwards data packet between computer network?

25) What is the speed of standard 10 base T cable?