13. a hypothesis must be both
a. tested and accepted
b. testable and falsifiable
c. variable and true
d. predicable and controlled

Aresearcher is studying the science of attractiveness and asks volunteer test subjects to rank what trait they find most attractive in a person what type of variable is the dependent variable in this experiment

According to the theory of punctuated equilibrium, at what rate does speciation occur? species change depending on the rate of natural selection. after periods of stasis, new species evolve relatively rapidly. species change slowly and eventually form new species. some species change quickly and others change slowly to balance the overall rate.

This is one of the five kingdoms in the older biological succession. organisms in this kingdom are prokaryotic