A 15-g sample of radioactive iodine decays in such a way that the mass remaining after t days is given by m(t) = 15e−0.073t,
where
m(t)
is measured in grams. After how many days is there only 5 g remaining?

Barney & noblet customers can choose to purchase a membership for $25 per year members receive 10% off all store purchases 1. how much would a member pay per year if he bought $50 worth of items each year? 2. write a slope-intercept equation that expresses how much a member pays per year using x to represent his purchases per year 3. how much would a member have to spend per year to pay off his membership fee?