EXAMPLE $8$ The height $($in feet$)$ at any time t $($in seconds$)$ of a projectile thrown vertically is h$($t$)=-16$t$^2+256$t $($a$)$ What is the projectile's average velocity for the first $5$ seconds of travel? $($b$)$ How fast is the projectile traveling $6$ seconds after it is thrown? How high is it$?($c$)$ How fast is the projectile traveling $10$ seconds after it is thrown? How high is it$?($d$)$ When is the maximum height reached by the projectile? What is its maximum height? $($e$)$ When does the projectile return to the ground and with what velocity?