Here, Function: h(t)= -16t² + 70t + 40
So, put the value of t, (time at which you want to calculate the height)
h(1) = -16(1)² + 70(1) + 40
h(1) = -16 + 110
h(1) = 94
Now, h(2) = -16(2)² + 70(2) + 40
h(2) = -64 + 180
h(2) = 116
h(3) = -16(3)² + 70(3) + 40
h(3) = -144 + 250
h(3) = 106
In short, Your height depends on time, and at each time it would be different, can be expressed by the coordinates on a Graph: (1, 94) (2, 116) (3, 106)
Hope this helps!