Physics tells us that an object projected at time t=0 from a point y0 feet above ground with an initial vertical velocity of v0 feet per second has a height above the ground after t seconds that is modeled by the function h(t)=−16t2 v0t y0 . At that same time t, the distance the object has traveled is modeled by the function d(t)=v1t , where v1 is the initial horizontal velocity.