hi 295Ja

Q1. You can use

directly, where g = 10 t = 3 and u = 10

This assumes s(0) = 0

Q2 The picture below is my view of this problem.

On the left we have the graph of the function for the base.

On the right a 3D represenation of the base with one slice shown rising up in a third dimension.

The slice has area half y^2 and thickness dx

So integrate these to get the volume.

Bob