Answer
324 ft
Work Step by Step
$s=16{{t}^{2}}$
For the height $\left( s \right)$,
The object falls for 4.5 seconds.
For $\left( s \right)$, put $\left( t=4.5\text{sec} \right)$ in the expression,
$\begin{align}
& s=16{{t}^{2}} \\
& =16\times {{\left( 4.5 \right)}^{2}} \\
& =16\times 4.5\times 4.5 \\
& =324
\end{align}$
Therefore, it is $324\text{ft}$ above the ground.
