4. A diver launches herself off a springboard. The height of the diver, in
metres, above the pool t seconds after launch can be modelled by the
function:
h(t) = 5t-10t² + 10, t≥ 0
a) How high is the springboard above the water? How do you know?
b) Use the model to find the time at which the diver hits the water.
c) Find the maximum height of the diver.
d) For how long is the diver above 10.5metres?
What do you do for D??