If in the number '97456231', the digits at the even positions are increased by 2 and the digits at the odd positions are decreased by 1, and then the digits are arranged in descending order (from left to right), which digit will be third to the right of the fifth digit from the right end?

If 2 is added to each odd digit and 1 is subtracted from each even digit in the number 7246158, what will be the sum of the digits that are third from the left and third from the right in the new number formed?

If 1 is added to each odd digit and 2 is subtracted from each even digit of the number 6847153, then which digit will be the second digit from the left in the new number formed?