A cyclist is training for an upcoming cycling road race and plans to adjust the weekly training mileage in the weeks leading up to the event. The function d(t) = 170 · (0.75)t models the weekly distance, d(t), in miles, after a given number of weeks, t.

Part A: Find the percent rate of change. Show all necessary steps. (2 points)

Part B: Explain the meaning of the percent rate of change in the context of the problem.