Juan owns a tree cutting machine service. For every 3 hours of tree-cutting, Peter charges $25.50. Select the equation that models the relationship between the total charge, y, and the number of hours, h, worked.
A. $25.50= 3h B. y= (3+h) - $25.50 C. y = 76.5h

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