A pomegranate is thrown from ground level straight up into the air at time $t=0$ with velocity 80 feet per second. Its height in feet at $t$ seconds is $f(t)=-16 t^2+80 t$. Find the time it hits the ground and the time it reaches its highest point.
Hits the ground when $t=$ (include units)
Reaches highest point when $t=$ (include units)
Maximum height = . (include units)