Astronomers have proposed the existence of an unexplained force that is causing the expansion of the universe to accelerate. what do they call this force?

In stage 2 farmers used the land primarily to grow food for their families and their small communities.

Astudent conducts an experiment to see how music affects plant growth. the student obtains four identical plants. each one is potted in the same type of soil and receives the same amount of sunlight and water each day. plant a listens to classical music for three hours each day. plant b listens to rock music for three hours each day. plant c listens to country music for three hours each day. plant d does not listen to any music at all. 2. based on the experiment in the scenario, which visual aid would be most in showing the change in the plants' heights over time? a. a pie chart b. a line graph c. a timeline d. a bar graph

The coco river is a natural border between nicaragua and which other country