The measure of a road’s slope is called the grade. the grade of a road is measured in a percentage, for how many vertical feet the road rises or declines over 100 feet. for example, a road with a grade incline of 5% means that for every 100 horizontal feet the road rises 5 vertical feet. which of the following is the slope of a road with a grade decline of 8%? select one: a. −252 b. 225 c. −225 d. 252