Physics
posted by Bill .
A stone, initially at rest, is dropped from the top of a building. On its way down, it passes a window that is 2.52m tall. It takes 0.134 seconds to pass the window. From how far above the top of the window was the stone dropped?

Let H be the distance from the top of the building to the top of the window.
Let T be the time for the stone to reach that point. g = 9.91 m/s^2
Here is what you knmow:
H = (1/2) g T^2
H + 2.25 = (1/2) g (T + 0.134)^2
Combining the two equations, you can eliminate H
2.25 = (1/2) g [0.268 T + 0.018]
Solve that for T; then compute H with one of the original equations.