Why do some types of cells have shorter cell cycles than others

Hurry which of these is true about index fossils? a) are very scarcely found b) used as guides in relative dating c) found in the youngest layer of the rock d) used as reference points in absolute dating

Which units ate used to measure both velocity and speed? check all that apply

The first generation of offspring from the cross of two parents is called the a.f1 generation b.f2 generation c.short generation d.p generation