Question

how do you solve for tr and tf?

Answer 1

V = Vo + g*Tr.

V = 0 = Final velocity.
Vo = Initial velocity.
g = -9.8 m/s^2.
Tr = Rise time, or time to reach max ht.

h = o.5g*Tf^2.
h = Ht.
g = 9.8m/s^2.
Tf = Fall time.

I hope this helps.