Jose and his friends dined in a Mexican restaurant. The cost of the meal was $20.50. What was the final cost after they paid 9.5% for the sale tax and 15% for the tip?

He mass of a single atom of carbon can be found by dividing the atomic mass (12.01 g) by 6.022 x 10^23. which is the mass of a single carbon atom, correctly written in scientific notation with the correct number of significant figures?