Sulfur dioxide:
a. creates a reddish-brown haze in the sky
b. is a secondary air pollutant
c. has an irritating odor and is colorless
d. is relatively harmless to the environment

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

What process creates gametes? a. fertilization b. mitosis c. meiosis

What is the difference between topsoil and clay?