The height of a falling object is given by: 400-39t-157e^(-t/4) with h in meters and t in seconds Assuming that the ground is a height h=0 how fast is the object moving at the instant it hits the ground? be accurate to one decimal point.
I keep getting 243.0 m/s but it is wrong if someone can help me out.

Question

The height of a falling object is given by: 400-39t-157e^(-t/4) with h in meters and t in seconds Assuming that the ground is a height h=0 how fast is the object moving at the instant it hits the ground? be accurate to one decimal point. 
I keep getting 243.0 m/s but it is wrong if someone can help me out.

whpalmer4 · Answer

What have you found for the value of $t$ where $h(t) = 0$?  How are you determining the speed at that time?