Pleas help!!!!

Barry has been watching the geese that live in his neighborhood. The number of geese changes each week.

n f(n)
1 56
2 28
3 14
4 7

Which function best shows the relationship between n and f(n)? (1 point)

f(n) = 28(0.5)^n

f(n) = 56(0.5)^n−1

f(n) = 56(0.5)^n

f(n) = 112(0.5)^n−1