Aradioactive isotope takes 80 minutes to decay from 64 grams to 4 grams. let y(t) denote the amount of the isotope (in grams) present after t minutes.
1. find the constant c and k such that y(t)=ce^-kt

2. how long do we have to wait (in minutes) if we want the mass of the isotope to drop below 1 gram?

Graph the system of inequalities presented here on your own paper, then use your graph to answer the following questions: y > 2x + 3y is less than negative 3 over 2 times x minus 4part a: describe the graph of the system, including shading and the types of lines graphed. provide a description of the solution area. (6 points)part b: is the point (â’4, 6) included in the solution area for the system? justify your answer mathematically. (4 points)