Answer:
7.35 Million
Explanation:
So you already have the function and all you have to do is find the years.
p(t)=3.98(1.02)^t
I'm thinking that you should find the difference between 2021 and 1990. The answer would be 31 and just substitute that from t.
p(t)=3.98(1.02)^31
From here you would jut plug this function into your calculator and get a final answer of:
7.35 Million
Hope this helped :)