Answer
$SWR = \infty$
Work Step by Step
In the case of total reflection, the amplitude of the reflected wave is the same as the amplitude of the incoming wave.
That is: $~~B = A$
We can find the SWR in this case:
$SWR = \frac{A+B}{A-B}$
$SWR = \frac{A+A}{A-A}$
$SWR = \frac{2A}{0}$
$SWR = \infty$
