Answer:
The explicit formula for f(n) is:

Step-by-step explanation:
The explicit formula is described by the following geometrical progression:

Answer:
Step-by-step explanation:
√20=√5*2*2
√20=2√5
Step-by-step explanation:
.......
.................
Answer:
unlikely
Step-by-step explanation:
5/31 = 0.1613 : 16.13% < 50% unlikely
8.1% is the exact interest rate