Inactive Tutor answered 05/19/20
This is an example of exponential growth. At the end of each month, you will have 1.02 times the number you had at the start of the month.
p(n) = p0 (1.02)n
p0 = initial population = 821
n = number of months elapsed from when the population was 821
p(n) = 821 (1.02)n
Plug into the equation the number of months (n) in half a year, 2 years, and 10 years, and evaluate.