Simplify the expression p(p^-7*q^3)^-2*q^-3
A. p/q^3
B. p^15/q^9
C.1/(p^9*q^2
D. p^14*q

Me because some of question i don’t understand

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?

Bocephus has a bag full of nickels and dimes. if there are 3 times as many dimes as nickels, and he has $\$36.05$ in his bag, how many nickels does he have?