14.9- The concentration of E. coli bacteria in a swimming area is monitored after a storm:

t	4	8	12	16	20	24
c	1600	1320	1000	890	650	560

The time is measured in hours following the end of the storm and the unit CFU is a colony forming unit. Use this data to estimate (a) the concentration at the end of the storm (t = 0) and (b) the time at which the concentration will reach 200 CFU/100 mL. Note that your choice of model should be consistent with the fact that negative concentrations are impossible and that the bacteria concentration always decreases with time.