Verbal | idioms- more and more , most

Following are the references from manhattan gmat sentence correction guide, chapter-idioms

right::He was THE SECOND MOST attractive AND THE MOST powerful.

wrong::He was THE SECOND MOST attractive AND MOST powerful.

Q1) can somebody explain why first one is right and the other one is wrong

RIGHT::MORE AND MORE we have observed violent robberies on weekends.
RIGHT::INCREASINGLY we have observed violent robberies on weekends.
SUSPECT::We observed 10% MORE robberies last month.

Q2)Please explain
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