pls help w b. also not sure if what ive written down is right

Pls Help W B Also Not Sure If What Ive Written Down Is Right class=

Answer :

Answer:

See below

Step-by-step explanation:

b) 200 ft = -16 (t-2)^2  + 400

      200 / 16 = (t-2)^2

           sqrt (12.5 ) = t-2

              2 + sqrt (12.5)  = t