Find the constant of proportionality for each graph. Choose all of the graphs that can be represent by the equation y = 3x.

THE ONE WITH THE PINK LINE IS A AND THE ONE UNDER IS B AND THE NEXT PICTURES TOP ONE IS C AN DTHE ONE UNDER C IS D

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