Answer:
Step-by-step explanation:
The composition A ○ A is equivalent to A(A(x)) which is the amount of the investment one year after the original amount matured (at one year). That is, it is the amount of the investment after 2 years. Its value is ...
A(A(x)) = 1.06(1.06x) = 1.06²x
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Similarly, ...
A ○ A ○ A = A(A(A(x))) = 1.06(1.06(1.06x)) = 1.06³x, and
A ○ A ○ A ○ A = A(A(A(A(x)))) = 1.06(1.06³x) = 1.06⁴x
These are the amounts after 3 and 4 years, respectively.