He function h(t) = –16t2 + 28t + 500 represents the height of a rock t seconds after it is propelled by a slingshot. What does h(3.2) represent?

the height of the rock 3.2 seconds before it reaches the ground
the time it takes the rock to reach the ground, or 3.2 seconds
the time it takes the rock to reach a height of 3.2 meters
the height of the rock 3.2 seconds after it is propelled