Without a control group there wouldn’t be any basis for knowing if a result is due to the variable being tested
Answer: use solar energy then
Explanation:
Answer: B. under use; it is a scarce resource.
Explanation:
Early settlers in the town of Dry Gulch drilled wells to pump as much water as they wanted from the single aquifer beneath the town. (An aquifer is an underground body of water.) As more people settled in Dry Gulch, the aquifer level fell and new wells had to be drilled deeper at higher cost.Residents of Dry Gulch have a private incentive to under use water because it is a scarce resource.
Answer:
Forestation.
Explanation:
When life is created on land where there originally was no life, wind brings over pioneer species, such as grasses. Over time, life takes advantage and grows bushes, trees, and so on.