4. Radioactive decay can be modeled by the equation where A is the amount at time t, A0 is the amount at time , and k is a constant. Write a MATLAB program that calculates the amount of a radioactive material. When executed, the program asks the user to enter the halflife of the material (in years), the current amount of the material (in lb), and the number of years t from now for which the amount should be calculated.

From this information the program first calculates the constant k and then the amount at t years. For output the program displays the message: “The amount of the material after XX years is XX kg” where XX are the corresponding numerical values. Use the program to determine how much plutonium-

239 (half-life 24,110 years) will be left from 50 lb after 500 years.