Atractor has a rear wheel with a 2-meter diameter and a front wheel with a 1-meter diameter. two points on the outer rims of the tires, a and b, are labeled in the picture. the height above the ground, in meters, of point a is a function of the distance, in meters, x, that the tractor moves forward. the graph of this function is shown. which function represents the height above the ground, in meters, of point b? a b(x)=0.5+cosx b b(x)=0.5+0.5cos(x2) c b(x)=0.5+0.5cosx d b(x)=0.5+0.5cos(2x)