DETAILS This exercise uses the radioactive decay model. The half-life of cesium-137 is 30 years. Suppose we have a 16-g sample. (a) Find a function m(t) = m 2 " that models the mass remaining after t years. m(t) = (b) Find a function m(t) = me" that models the mass remaining after t years. (Round your / value to four decimal places.) m(t)= (c) How much of the sample will remain after 79 years? (Round your answer to one decimal place.) g (d) After how many years will only 2 g of the sample remain? (Round your answer to the nearest whole number.) yr NO REAL SOLUTION.)