Sunita carries out an experiment to investigate diffusion. she uses water and a food dye to find out how the volume of water used affects the time the dye takes to spread evenly through the water. her prediction is that the more water she uses, the longer the time needed for the dye to spread through it. which variable will she change?

Sunita will change the variable water.

Explanation:

Sunita have to change the variable water to perform this experiment of diffusion.This is because she is going to predict that more water she uses longer the time needed for the dye to spread through it.

 As a result she is increasing the amount of water to observe the effect of diffusible substance on diffusion with time.

its first and third is your answer i did the qustion the fourth isnt right