Answer:
Its vertical V = sqrt.(2gh) = sqrt.(19.6 x 31) = 24.65m/sec.
a) Sqrt.(24.6^2 + 13^2) = 27.8m/sec.
Time to max. height = (v/g) = (13/9.8) = 1.326 secs.
Height gain = 1/2 (t^2 x g) = 8.6 metres.
b) V at ground = sqrt.(2gh) = sqrt.(19.6(31 + 8.6)) = 27.86m/sec.
c) Since it will be going 13m/sec. in (b) as it falls to the building height, the V at the ground will be the same (27.86m/sec.).
Explanation: