Question

Someone help me out. Christine wants to see if different types of salt - rock salt , table salt , and kosher salt - have an effect on the time it takes for ice to melt. She places the same amount of ice, and a different type of salt, in each of three cups. Controlled variable?

A) Time it took for the ice to melt
B) Types of salt
C) Amount of ice in each cup
D) Inference

Answer 1

I would say, C. Because an controlled variable is an experimental element which is constant and unchanged throughout the course of the investigation.