An accident at a nuclear power plant has left the surrounding area polluted with radioactive material that decays naturally. The initial amount of radioactive material present is 42 su (safe units), and 5 months later it is still 31 su. a.) write a formula giving the amount A(t) of radioactive material (in su) remaining after t months. (Use integers or decimals for any numbers in the expression. Round to three decimal places needed.) b.) what amount of radioactive material will remain after 11 months? c.) how long will it be until A = 1 su, so it is safe for people to return to the area?

An accident at a nuclear power plant has left the surrounding area polluted with radioactive material that decays naturally. The initial amount of radioactive material present is 42 su (safe units), and 5 months later it is still 31 su. a.) write a formula giving the amount A(t) of radioactive material (in su) remaining after t months. (Use integers or decimals for any numbers in the expression. Round to three decimal places needed.) b.) what amount of radioactive material will remain after 11 months? c.) how long will it be until A = 1 su, so it is safe for people to return to the area?