The two lower chambers of the human heart are known as: a.
atriums
c.
auricles
b.
ventricles
d.
blood vessels

Barbara is converting 78°f to degrees celsius. first, she subtracts 32 from 78. what is the next step?

Which of the following is a possible reason for sleep? a) growth b)digestive c)speed d)intelligence

1. variations in a population of moths allow for some of its members to be able to adapt to environmental changes. the better adapted of the moths will be able to survive the change and thus prevail as the “fittest” of the species. (a) describe three mechanisms in which variation can occur within a species population. (b) explain which mechanism or mechanisms would be responsible for the survival of a population of peppered moths better than white moths in an environment affected by industrial soot. justify your answer.