Question

1. the unit of time used most commonly by physicists and other scientists is the:

a. second.
b. minute.
c. hour.
d. light year.

Explanation:

In the International System of Units (SI), the second is the base - unit of time and is most commonly used by physicists and other scientists for precise measurements and calculations. Minutes and hours are larger units, and a light - year is a unit of distance, not time.

Answer:

A. second