Final answer:
To solve for rate in the distance formula d = rt, the equation needs to be rearranged. The correct rearrangement is r = d/t, where rate equals distance divided by time.
Step-by-step explanation:
To solve for rate in the distance formula, d = rt, we need to rearrange the equation. The correct rearrangement is option a) r = d/t. This means that the rate is equal to the distance divided by the time.