What is the independent and dependent variable in this paragraph?

homer notices that his shower is covered in a strange green slime.his friend Barney tells him that coconut juice will get rid of the green slime.homer decides to check this out by spraying half of the shower with coconut juice and the half of the shower with water.afiter 3 day of treatment there is no change in the apprearance of the green slime on either side of the shower.