The sales S (in billions of dollars) for Starbucks from 2009 through 2014 can be modeled by the exponential function
S(t) = 3.71(1.112)t
where t is the time in years, with
t = 9
corresponding to 2009.† (Round your answers to two decimal places.)
(a) Use the model to estimate the sales in 2019 in billions of dollars.
$
billion

(b) Use the model to estimate the sales in 2023 in billions of dollars.
$
billion