Answer:
He needs to travel at the speed of 68 miles per hour.
Explanation:
306 miles is the distance. 4.5h is the time. You want to find the rate.
D = RT
306 = R×4.5
R×4.5 = 306
R = 306 ÷ 4.5
= 68
He needs to travel at the speed of 68 miles per hour.