the answer
the modeled function is c(n) = (5)^(n − 1)
It was assumed that on the first day, there were 103 likes, it can be considered as C(1), such that C(1) = 103 likes
therefore, the he function that shows the number of likes each day is
C(n) = 103(5) ^(n − 1),
proof:
C(1) = 103(5) ^(1 − 1) =103(5) ^(0), but (5) ^(0) = 1, so C(1) = 103 likes