An independent variable is: A. Remain the same to make an experiment a fair test.
O B. Measured to show the effect of a change.
C. Collected to draw conclusions.
D. Changed to test a hypothesis.

Where is having brightly colored feathers that attract mates most clearly an adaptation for a bird? a. a forest with dense vegetation b. a sandy beach beside an ocean c. a snowy tundra with little vegetation d. a swamp with many hawks that eat birds