Answer:
Part A:
8 x 7 = 56; 56 x 10 = 560
Part B:
504
Part A & B explanation:
If you notice, there are no decimals in the answers so it's clear they round them. 8.4 rounded is 8 & 6.9 rounded is 7. To find the area of a singular rectangle is length x width. 8 x 7 = 56. In part A the directions say "best estimate" signaling that it isn't the exact answer you're looking for. 8 x 7 = 56; 56 x 9 = 504 would be the exact answer. (Answer for part b).Therefore, the answer for part A is 8 x 7 = 56; 56 x 10 = 560. Because 560 is the closest to 504 on the board.
Hope this helped <3