Please i need your help, i suck at biology and my dad isnt helping much

In a certain ecosystem owls are predators for mice. the owl population increases and they eat more mice this causes the mouse population to decrease what happens next? a.the birth of mice increases. b. the birth rate of owls increases c. the population of owls decreases d. the population of mice increases

Acquired mutations can result from radiation pollution toxins inheritence select all that apply

Veins have a much lower blood pressure than arteries. which of these prevents backflow of blood in veins? a. pressure applied by the heart b. one–way valves in veins c. thin muscular walls of veins