Suppose that two pieces of the tape shown above are used to make this $(E)$ spectrum:

The "edge step" is the size of the jump at the onset of absorption and is found by regressing lines to the

pre$-$edge and post$-$edge regions of the data, as shown, and measuring their vertical spacing at the edge energy.

Question: With a clear explanation, what size would you expect the edge step to be if the data were

measured with:

$($a$)$ a stack of three pieces of tape?

$($b$)$ one piece of tape?