Which of these expressions equal 15 when x = 1/2 and y = 3. Choose all that apply

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?

You have 17 cats that live in houses on your street, 24 dogs, 3 fish, and 4 hamsters. what percent of animals on your block are dogs?

Perry observes the opposite parallel walls of a room in how many lines do the plains containing the walls intersect