Can someone Help me with this Math Problem plz??!!?

An Object is thrown straight up into the air. The Equation:



s=s(t)= -16t^2 + 32t +48



Gives the distance, S(in feet), the object is above the ground ';t'; seconds after it is thrown.



1) How high above the ground is the object at t=3 seconds ??



2)How long, in seconds, does it take for the ball to hit the ground ??







Please guys help me ;)

I'll appreciate that.

ThanksCan someone Help me with this Math Problem plz??!!?
I know what 36 x 4 is... 144!!!