Given the atomic weights of carbon, 12.01; hydrogen, 1.01; and oxygen, 16.0, what is the molar mass of glucose?
a) 166.18 grams
b) 174.12 grams
c) 180.18 grams
d) 250.12 grams

The molar mass of any molecule is the sum of its constituent elements atomic masses. In glucose, there are six carbon atoms, twelve hydrogen atoms, and six oxygen atoms. If we show this mathematically:
6(12.01 g/mol) + 12(1.01 g/mol) + 6(16.00 g/mol) = 180.18 grams/mole is the molar mass of glucose
The answer is C) 180.18 grams

You just multiply the atomic weight by how many mol of each element are in a mol of the molecule. 

(6mol carbon * 12.01g/mol carbon) + (12 mol Hydrogen * 1.01g/mol) + (6 mol oxygen * 16.0g/mol oxygen) = 180.18 g / mol glucose.
I hope my answer helped you.