The two main sources of genetic variation are shuffling and

Which of the following describes a boom period? a. as one population increases, another population decreases. b. as one population increases, the other population also increases. c. as one population decreases, another population increases. d. as one population decreases, another population also decreases

24. how are vaccines used to keep people healthy?

Which of the following is not a technology that can be used to conserve resources? a. hydropower b. volcanic power c. natural gas d. geothermal select the best answer from the choices provided a b c d