Dams are used to produce hydroelectric power. which of these best describes the impact of a dam on the environment?
a. it causes air pollution.
b. it reduces the level of groundwater.
c. it causes changes in the river ecosystem.
d. it reduces the level of oxygen in river water.

Which of the following would be the best hypothesis for this experiment? a) use of the ginko biloba extract improves clinical outcomes when administered to patients with t2d. b) ginko biloba improves clinical outcomes of diabetes patients when combined with metformin. c) diabetes in patients is worsened when ginko biloba is taken in conjunction with metformin. d)the use of ginko biloba to treat t2d in combination with metformin lowers the cost of t2d treatment. ginko biloba shows benefits against t2d when combined with plant extracts as compared to other treatments.