Estimate (a) how long it took king kong to fall straight down from the top of the empire state building (380m high), and (b) his velocity just before \"landing\"? .

So the answer among the following questions in you problem that ask to find the time it took when King Kong fall straight down from the top of the Empire states building and his velocity before landing and the time would be 8.81 seconds and and its velocity is equals to 86.43m/s.  I hope this would help  

Initial velocity,  u = 4.9 m/sfinal velocity = v m/sinitial height,  h₁ =  245 m    final height, h₂ = 0a = -9.8  m/s²time taken = t secondss = ut + 0.5at²⇒  (h₂-h₁) = ut + 0.5at²⇒  0-245 = 4.9t + 0.5×(-9.8)×t²⇒ -245 = 4.9t - 4.9t²⇒ 4.9t² -4.9t -245 =0solving it, we get   t = 7.59sv  = u +  at = 4.9 -9.8×7.59 = 4.9 - 74.38 = -69.48 m/svelocity is  69.48 m/s downward