Answer:
The money Javier earned installing doors.
Step-by-step explanation:
The problem statement gives insufficient information to answer the question with certainty.
The $56 extra earnings from door installation seems to match the 56 added as a term in Javier's pay, so we assume they are related. There is nothing else in the problem statement suggesting that to be the case.
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Comment on this problem
The problem fails to teach anything about math or critical thinking. Rather, it requires a student to jump to conclusions without any basis in reasoning. If the rest of the curriculum materials are like this, they should be rejected.