Acountries population in 1992 was 39 million in 1997 it was 42 million estimate the population in 2009 is an exponential growth formula

First we need to find the growth rate
The exponential growth formula is
P=A e^rt
P population in 1997=42 million
A population in 1992=39 million
E constant
R growth rate ?
T time 5years (1997-1992)
Solve the formula for R
R= [log(p/A)÷log (e)]÷t
R=(log(42÷39)÷log(e))÷5
R=0.015

Now estimate the population in 2009 using the same formula
P=A e^rt
P ?
A 42 million
R 0.015
T 12 years (2009-1997)
E constant
P=42×e^(0.015×12)
P=50.28 million round your answer to get 50 million

B. because the 7 represents "seven times", x represents "a number", 12 represents "plus twelve", and -4 represents "minus four"