5.20 lab: driving cost - functions write a function drivingcost() with input parameters drivenmiles, milespergallon, and dollarspergallon, that returns the dollar cost to drive those miles. all items are of type double. if the function is called with 50 20.0 3.1599, the function returns 7.89975. define that function in a program whose inputs are the car's miles/gallon and the gas dollars/gallon (both doubles). output the gas cost for 10 miles, 50 miles, and 400 miles, by calling your drivingcost function three times. output each floating-point value with two digits after the decimal point, which can be achieved by executing cout < < fixed < < setprecision(2); once before all other cout statements. ex: if the input is: 20.0 3.1599 the output is: 1.58 7.90 63.20 your program must define and call a function: double drivingcost(double drivenmiles, double milespergallon, double dollarspergallon) note: this is a lab from a previous chapter that now requires the use of a function. lab activity 5.20.1: lab: driving cost - functions 8 / 10