What is a arbitrary signal?

A signal x(t) is called an energy signal , if the energy is finite and the power is zero. A signal x(t) is called an power signal , if the power is finite and the energy is infinite.

Voice signals are analog signals, whereas computer signals are digital .

yes. Digital signals means discrete which varies instantaneously as binary.

A: while a step can be of both polarity but it is a level change and it is DC LEVELS

a digital signal requires an amplifier, which introduces noise into signal No, an analog signal is generated by sensors such as a microphone and has a shape that resembles what is transmitted so much...