What is the average rate of change for the function f(x)=6x+17 over the interval 0 is greater than or equal to x is greater than or equal to 2?

Technicians have installed a center pivot, circular irrigator for a farm that covers 25 acres. a.) how long is the irrigation boom (in feet) from the center pivot to its farthest extent? b.) if the irrigation boom makes 4 full revolutions in a day, how many miles does the end of the boom travel in 5 days?