a, and b

A chemist has a 100-gram sample of a radioactive material. He records the amount of (a) Treating week, x, as the independent variable, use a graphing utility to fit an radioactive material every week for 6 weeks and obtains the following data. Complete exponential function to the data. parts (a) (f). y = ab= Weight, y Week, x (Round to four decimal places as needed.) (in grams) 0 100.0 1 85.8 (b) Express the function found in part (a) in the form A(t) = Ap ek. 2 71.7 3 63.7 A(t) = 4 52.7 (Round to four decimal places as needed.) 44.9 6 38.4 (c) Graph the data together with the exponential function found in part (a) or part (b) on a scatter diagram. Which graph correctly illustrates the exponential model found for this data