Fuad’s model racing car drives at an average speed of 3 feet per second. Fuad records the distances and times in a table like the one shown below.

Speed of Model Race Car
Distance (ft.)
3

Time (s)
1


At this rate, how long will it take the car to travel 21 feet?
3.0 seconds
6.3 seconds
7.0 seconds
14.3 seconds