If u drop a bouncy ball off a roof and it takes 1.2 seconds to hit the ground how tall is the roof

Here's the formula to use:

D = 1/2 A T²

Distance = (1/2) (Acceleration) (time) ²

Now let's use it:

Distance = (1/2) (9.8 m/s² for Earth gravity) (1.2 seconds) ²

Distance = (4.9 m/s²) (1.44 sec²)

Distance = (4.9 x 1.44) (m-s² / s²)

Distance = 7.06 meters