Answer
a) $-16t(t-4)$
b) 48 feet
c) The common factor of $-16t$ was factored out, which allows the two expressions to be the same.
Work Step by Step
a)
$-16t^2+64t$
$-16t(t-4)$
b)
$h(t)=-16t^2+64t$
$h(1)=-16*1^2+64*1$
$h(1)=-16*1+64$
$h(1)=-16+64$
$h(1)=48$
$-16t(t-4)$
$-16*1(1-4)$
$-16*-3$
$48$