The amount of cytosine in dna should always equal the amount of what

The series of transgressions and regressions that produce cyclothems were likely produced by

Ais a landform that is formed at the mouth of a river from the deposition of sediment carried by the river as the water flows.

Amale bird-of-paradise uses a dance to attract mates in which it flaps its tail feathers on the ground and jumps around a potential female mate. a different male bird-of-paradise does a similar dance but it jumps around the female in the opposite direction. the female bird is only attracted to one style of dance, in one direction.