2 students are experimenting to see if the amount of water affects who quickly it heats to 100*C. They decided to heat one beaker of 500 mL of water to 100*. They heat the second beaker of 250 mL of water to 100*C. They time how long it takes each to reach the desired temperature. They record their results. 1. What is the independent variable in the experiment above?

A. 500 mL of water
B. the amount of water
C. heating the water to different temperatures
D. how quickly the food dye spreads.