7. In your own words, explain how to find the local maximums and minimums of a function f (x) using the first derivative test. 8. Use an example to help you explain how to determine the oblique asymptote of a function. 9 A pebble is thrown vertically upwards from the top of a cliff that is 30 m high. The pebble's height, in metres, in relation to the top of the cliff at any time t, is given by: h (t) = -5t2 + 25t + 30. Find the pebble's velocity on impact at the base of the cliff (i.e. when it hits the ground)