What are the answers ​

Which expression is equivalent to7_/x^2 ÷ 5_/y^3? assume y# 0

Ascientist has 50 grams of a radioactive element. the amount of radioactive element remaining after t days can be determined using the equation (1) after two days the scientist receives a second shipment of 50 grams of the same element. the equation used to represent the amount of shipment 2 remaining after t days is 10) - 50 which of the following is an equivalent form of the expression for the amount remaining in shipment 2? what’s the answer?

Whats the theoretical probability of popping a polka dot balloon? express your answer as a fraction, decimal and percent solid 15 polka dot 5 striped 17 plzz me due tomorrow