When a multistage amplifier is to amplify d.c. signal, then one must use coupling

A. It is a simple unit B. Calculations become easy C. Human ear response is logarithmic D. None of the above

A. There is considerable power loss B. There is hum in the output C. Electrical size of coupling capacitor becomes very large D. None of the above

A. 3 db B. 66 db C. 20 db D. 200 db

A. 5 db B. 2 db C. 10 db D. 3 db