Solids maintain their shapes explain

here you go

Explanation:

The intermolecular forces of attraction in solids hold the particles so tightly in place that they cannot pull away from each other to expand their volume nor can they flow past one another to change shape. Therefore, solids hold their own shape and volume regardless of their containe

if you already have the answer to (a), then just work out how many periods there are in 1 minute, and that's the answer to (c).

layers of the earth affect the waves and these effects are seen on instruiments such as seimometers