Answer:
2nd option
Step-by-step explanation:
Given
2x - 8y + 3x² + 7y - 12x ← collect like terms
= 3x² + (2x - 12x) + (- 8y + 7y)
= 3x² + (- 10x) + (- y)
= 3x² - 10x - y
112
Monday=14
Tuesday=2x14=28
Wednesday= 2x28=56
Thursday= 2x56=112
so he is incorrect.