Answer:
(1) 56 miles/hour
Explanation:
We need to find the average rate of change from t = 2 to t = 9.
At t = 2 hours, d = 106 miles.
At t = 9 hours, d = 498 miles.
The average rate of change in function f(x) from x = a to x = b is
[f(b) - f(a)]/(b - a)
average rate of change from t = 2 to t = 9 =
(498 - 106)/(9 - 2) = 392/7 = 56
Answer: (1) 56 miles/hour