i have attempted a,b,c but got bit unsure about the answer for d. are my calculations correct? and if anyone could help with part d.

(a) s= -u^2/2a

= -25^2/2 x 9.8

= 31.9m

(b) t = -u/a

t=-25/-9.8

t= 2.55secs to reach max,therefore 5.1secs to return to thrower

(c) v^2=u^2+2as

v^2=25^2+2(-9.8x5)

v=sqrt (527)

v=23ms^-1

(d) this was the one i was unsure about? i tried getin an estimate from a graphical method and got 15metres @ 4secs?