Chemistry question- boiling point elevation. please help?

The boiling point of carbon tetrachloride is 76.8 oC. A given solution contains 6.49 g of a nonvolatile nonelectrolyte in 381 g of CCl4. The solution boils at 78.1 oC. What is the gram molecular mass of the solute? (Boiling point constant for CCl4 is 5.03 oC/molal)