\input epsf
\nopagenumbers
\magnification=\magstep1

\noindent {\bf Problem statement} After a softball game, the winning
pitcher throws the ball straight up in the air. The height $s$ of the
ball in feet is given by the formula $s=5+48t-16t^2$, where $t$ is the
time after release (measured in seconds).

\medskip

\noindent a) The formula is valid only until the ball hits the ground.
When does that happen? 

\medskip

\noindent b) Find the instantaneous velocity of the ball at the
following instants: $t=1$, $t=2$ and $t=3$.

\medskip

\noindent c) When do you think that the ball reaches its highest
point?  Check your guess by computing the instantaneous velocity at
that instant. How high does the ball get?













\vfil\eject\end

