Astudent wants to test the effect of nitrogen rich fertilizers on the growth of rose bushes. which of the following is a variable that must be kept constant?

growth of the rose bush
amount of water the rose bush receives
the use of nitrogen rich fertilizer

Elephants in the savanna regions of africa dig holes in dried up river beds to reach water lying just below the surface. these holes provide drinking water for other animals as well. so, without the elephants, many animals might otherwise die from lack of water during the dry season. the location in which the elephants live is an example of a/n and the role they play in creating water holes is an example of a a) ecosystem; habitat b) community; niche c) habitat; niche d) niche; habitat

Which of the following forest management practices is best for reestablishing areas of forest?

Which of these outcomes is a negative impact of postindustrial societies on the environment? a. nomadic ways b. overpopulation c. overgrazing d. resource renewal