Hi , the answer is 52% , because 13 divided by 25 equals to 0.52 , we move the decimal two spaces to the right , so the answer is 52.
Sandwich cost $7.70 and the soda costs $2.20.
One of the product rules for exponents was used.

Or, you can consider that the definition of an exponent and the associative and commutative properties of multiplication were used.
10 whole sandwiches can be made with 2 pounds of cheese if each sandwhich has 3 ounces of cheese on it.
2 pounds = 32 ounces
32/3 = 10.67