A. He should add shells that are different colors, but the same size and type, to the tank and observe which shells the hermit crabs choose.
Durning an experiment you need to keep everything the same but only change the certain things based on your theory.
Such as how the student wanted to see if the color attracted the crab. If he had changed the size and type of the shell then the crab would have chosen the bigger one as they tend to grow into larger shells.
Answer:
A
Explanation:
Energy cannot be created nor destroyed.
Answer:
Blood vessels which help the body carry red blood cells throughout the bodies functions.
Explanation:
Capillaries, the smallest and most numerous of the blood vessels, form the connection between the vessels that carry blood away from the heart (arteries) and the vessels that return blood to the heart (veins). The primary function of capillaries is the exchange of materials between the blood and tissue cells.
I think it is erosion (2) because erosion removes soil, rock, and dissolved material.
