Answer:
2
Explanation:
A is on the line QA', which is 1.25+1.25 = 2.50 units long*. Thus the scale factor is ...
QA'/QA = 2.50/1.25 = 2
The scale factor is 2.
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* There are two points on the line QA that are 1.25 units from A. One of them is point Q. If A' is coincident with Q, then the scale factor is 0, and line segment A'B' is the single point Q. We don't believe that is intended to be the case, so we assume that point A' is farther along AQ, hence 2.5 units from Q.