Question 312141
The formula s = 16t2 is used to approximate the distance s, in feet, that an object falls freely (from rest) in t seconds. Use this formula to solve the problem. (Round answer to the nearest tenth.) 
A man drops his keys off a building 1420 ft high. How long does it take the keys, falling freely, to hit the ground
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{{{s = 16t^2 }}}
Plug in the given info:
{{{1420 = 16t^2 }}}
{{{ 88.75 = t^2 }}}
{{{ 9.4 = t }}}  (seconds)