What statement is one of the three parts of a cell theory? a. all cells come from another cell b. cells grow like crystals c. cells assemble themselves from whatever is around d. plant and animal cells are exactly alike

I might be wrong but i believe the answer would be A.

Explanation:

I think its A. because:

The unified cell theory states that all living things are composed of one or more cells; the cell is the basic unit of life; and new cells arise from existing cells.

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"

the formula mass of a molecule or a compound is the sum of the atomic weights of the atoms in its empirical formula

(that's what i know about formula mass)