In Physics, the students solve this problem by applying the Energy Conservation  Law


 +  = ,


where m is the mass of the body, v is the starting velocity (directed vertically up),  V = the final velocity directed 
vertically down (the value under the question) and g = 32 ft/s^2 given in the condition.


Canceling "m" in both sides and simplifying, you get


V =  = ,


and what you need to do is to use your calculator.