2.
stay at least__behind the vehicle ahead of you at all
times.
a. 3 seconds
b. 4 seconds
c. 3 car lengths
d. 4 car lengths

Both a & b  

A. 3 seconds

B. 4 seconds

Explanation:

3 seconds rule is to be followed when the road is dry. So it means that we are very close to the vehicle which is in the front and we need to adjust the speed of the vehicle so that we maintain atleast 3 seconds delay with the front vehicle. It is one of the safety aspect / traffic rule to be learnt.

4 seconds rule is to leave 4 seconds gap between our vehicle and the vehicle which is moving front. This is done so that we don’t dash the vehicle if the front vehicle has to be stopped immediately and we have breathing time to put the break. It is mainly used in frosty climate.

answer; i believe the correct answer is : communicate safe work practices;