ANS:A - True

The time required for a pulse to go from a low state to a high state is called the rise time, and the time required for the pulse to return to zero is called the fall time.

It is common practice to measure the rise and fall time between 10 percent amplitude and 90 percent amplitude. The reason for taking the measurements in these points is due to the non-linear shape of the pulse in the first 10 percent and final 90 percent of the rise and fall amplitudes.

The pulse width is defined as the duration of the pulse. To be more specific, it is the time between the 50 percent amplitude point on both the pulse rise and fall.