36, 60, 62, 64 are the missing numbers of the pattern.
Answer:

Step-by-step explanation:
Given
--- initial
-- rate
Value after a year = $20.70
Required
Expression to calculate its value after y years
This is calculated using:

Where

Substitute
in 



Substitute
and
in 

I don't see a b or an m in this function, but generally, a linear function is of the form ax+b. The b in this equation (not sure if it is the same as your b), controls the shift of the function. Lower b by 3, the graph shifts down by 3.
So unless there is a minus sign before b, it has to be lowered by 3. (If there is a minus sign, it has to be increased by 3).
Not enough information- the coupon will only be worth 24% after tax though.
Answer:
For example, if given a graph, you could use the vertical line test; if a vertical line intersects the graph more than once, then the relation that the graph represents is not a function.
Hope this helped