12. The population of a city is growing at the rate o \( 0.4 \% \) per year. In \( 2007 \) , the population was \( 83,000 \) people. Which function represents the towhin's population "t" years after \( 2007 \) ?
A. \( y = 83 ( 1.04 ) ^ { t } \)
B. \( y = 83 ( 1.4 ) ^ { t } \)
C. \( y = 83000 ( 1.4 ) ^ { t } \)
D. \( y = 83000 ( 1.004 ) ^ { t }\)
as initial population is 83000
and it is increasing at the rate 0.4%
so
y = 83000(1.4 )\(^t\)
Joe earns \( \$ 9 \) per hour. He worked \( x \) hours on both Wednesday and Friday, and \( 8 \) hours on both Tuesday and Saturday. Write an expression to represent how much Joe earned.
If a virus spreads at a rate that can be modeled by the exponential function \( A ( t ) = ae ^ { r t } \) , how many people will be infected after \( 5 \) days if initially \( 3 \) people are infected and the growth rate is \( 40 \% \) ?
