Why was there such a lack of diversity in life during precambrian time?

There is a liquid capsule inside a cup full of liquid. the cup full of liquid has salt in it and the liquid capsule has no salt in it. in which direction will the solvent flow? a. the salt does not have to move b. from the capsule to the larger cup c. equally between the capsule and the cup d. from the larger cup to the capsule

Plz ! ive been stuck on this forever

What best describes the dropping height of a ball that bounces back up to a height of 45 cm