Last physics problem for the day I promise :)

A stone falls from rest from the top of a cliff. A second stone is thrown downward from the same height 3.1s later with an initial speed of 60.76m/s. They hit the ground at the same time.

The acceleration of gravity is 9.8m/s/s.

a) How long does it take the first stone to hit the ground? Answer in units of s.

b) How high is the cliff? Answer in units of m.

Based on the information given it definitely seems possible to solve this problem, but I just can't seem to put the information together.