Let's start with the fact that this is a function. Each element of Set A is paired with exactly one element of Set B.
This makes Set A the set of inputs and Set B the set of outputs.
There are a lot of other boxes to pick from, so I'm not sure what else you'd need to pick to make your answer correct.
The correct answer is A square root of 41
891 were sold
.55x1800= 990
10% of 990 roses is 99 (99 is left over)
990-99= 891
The length is 12, because if it's 9 inches wide it has two sides of 9 inches which is 18. Then subtract that from the intial value 42 to get 24. After, you divide 24 by 2 due to there being 2 sides of the box and 24 is the sum of both sides. Hopethis helps!