Question

how is speed calculated?
multiply velocity by displacement
divide velocity by displacement
multiply distance by time
divide distance by time

Explanation:

Speed is defined as the rate of change of position. The formula for speed is $s=\frac{d}{t}$, where $s$ is speed, $d$ is distance, and $t$ is time. So speed is calculated by dividing distance by time.

Answer:

Divide distance by time.