The price of products may increase due to inflation and decrease due to depreciation. Derek is studying the change in the price of two products, A and B, over time.

The price f(x), in dollars, of product A after x years is represented by the function below:

f(x) = 12500(0.82)x

Part A:Is the price of product A increasing or decreasing and by what percentage per year? Justify your answer. (5 points)

Part B:The table below shows the price f(t), in dollars, of product B after t years:

t (number of years)1234f(t) (price in dollars)5600 3136 1756.16 983.45

Which product recorded a greater percentage change in price over the previous year? Justify your answer. (5 points)