Answer
a. nonlinear.
b. No, see "Work Step by Step" down below.
Work Step by Step
a. If you look at the table, you will find that the equation of this function is
$A = (\frac{1}{2})^n$. Therefore, this function is not linear.
b. $A$ will never be zero. it will go on and on and on and be very close to zero, but it won't ever be zero.
