! WILL MARK THE BRAINLIEST! Jennifer is attempting to determine which type of soap works best. She takes four plates with roughly the same amount of leftover lasagna on them and washes one with Dawn soap, the second with Delta Classic soap, the third with Moen soap, and the fourth with water.

Figure out the Controlled Variable, Dependant Variable, Independent Variable, Constant Variable

!WILL MARK THE BRAINLIEST!

more info ? ? i don't understand what the question is

explanation:

1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%