Please help me to do this problem since I don't know how to do it. Please don't answer with links that don't work please this is important. Help me and I gonna appreciate you great helpplease.

If the sales price of a dvd is $20 and the markup is 34%, what is the cost of the dvd?

How many terms does the polynomial x^2 y^2 have

The weight of a radioactive isotope was 96 grams at the start of an experiment. after one hour, the weight of the isotope was half of its initial weight. after two hours, the weight of the isotope was half of its weight the previous hour. if this pattern continues, which of the following graphs represents the weight of the radioactive isotope over time? a. graph w b. graph x c. graph y d. graph z