Question

1. ddt and other pesticides used over 50 years ago are still affecting the environment today. scientists have found these substances in recent glacier runoff. glacier runoff occurs during the summer, when precipitation that has fallen on glaciers during the winter is released. ice layers from existing glaciers have been analyzed. the results of this analysis show that the concentrations of ddt and other pesticides were highest about 10 years after the use of these substances was banned.

this information shows that:
a. ddt and other pesticides cause glacier runoff during the summer.
b. it takes humans over 50 years to analyze a glacier.
c. precipitation helps to break down pesticides.
d. the decision of one human generation may have an impact on future generations.

a
b
c
d

43.
1 point

1. when fertilizers run off farmland into streams and ponds, the nitrogen content of the water increases. this can lead to rapid growth of algae in a process called eutrophication. how can this process affect other organisms in the water?

a. oxygen is used up as algae is decomposed, reducing the amount available to other organisms
b. the water becomes better able to support aerobic organisms.
c. the algae provide food for fishes and other organisms, leading to decreased algae populations.
d. the extra nitrogen provides additional food for the other organisms, increasing their population

Explanation:

Answer:

D. the decision of one human generation may have an impact on future generations.
A. Oxygen is used up as algae is decomposed, reducing the amount available to other organisms.