Need help very fast on this hard question

A sample of baking soda contains 34.48 g of sodium, 1.51 g of hydrogen, 18.02 g of carbon, and 72.00 g of oxygen.

a. What is the total mass of the sample? ______________g

Remember the addition rule for sigfigs

b. What is the percent by mass of each element in baking soda? Remember the sigfig rule for division

Sodium ______________%

Hydrogen ______________%

Carbon ______________%

Oxygen ______________%

Follow sigfig rules for division; answers will be marked incorrect by the computer if you do not use the correct sigfigs in your final answer