Physics
posted by Sam .
a) A cannonball is fired horizontally from the top of a cliff. The cannon is at height H = 100 m above ground level, and the ball is fired with initial horizontal speed v_0. Assume acceleration due to gravity to be g = 9.80 m/s^2. Assume that the cannon is fired at time t = 0 and that the cannonball hits the ground at time tg. What is the y position of the cannonball at the time tg/2?
I got 75m and I know that one is right.
I need help with part b
Given that the projectile lands at a distance = 110 from the cliff, as shown in the figure, find the initial speed of the projectile, .

If you found tg, the time in the air, then
110=horizontalvelocity*tg 
I found tg to be 4.5. Is it 24.44

yes, watch the significant digits.

alalalalalalaaaaaa