4. Why are coral reefs only found in tropical water? * (1 Point)
They need cold water with little sun
They need deep water and humid temperatures
They require shallow waters where the sun can reach them

Ronald wants to see if a new shower cleaner works better in removing soap than his old cleaner. he uses the new cleaner on one half of the shower tiles and his old cleaner on the other half. identify the independent and dependent variables in this experiment. enter your answer in the space provided.