a) The cost of first-class postage stamp was 4 in 1964 and 36 in 2010. This increase represents exponential growth. Write the function S for the cost of a stamp t years after 1964 (t= 0). b) What was the growth rate in the cost? c) Predict the cost of a first-class postage stamp in 2016, 2019, and 2022. d) The Forever Stamp is always valid as first-class postage on standard envelopes weighing 1 ounce or less, regardless of any subsequent increases in the first-class rate. An advertising firm spent $3600 on 10,000 first-class postage stamps in 2009. Knowing it will need 10,000 first-class stamps in each of the years 2010-2023, it decides at the beginning of 2010 to try to save money by spending $3600 on 10,000 Forever Stamps, but also buying enough of the stamps to cover the years 2011 through 2023. Assuming there is a postage increase in each of the years 2016, 2019, and 2022 to the cost predicted in part (C), how much money will the firm save by buying the stamps