In bowling, the total set of pins is {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}.
From the rolls given:
- In the first roll, you knocked down pins {1, 5, 7, 9}.
- In the second roll, you knocked down pins {4, 8}.
So, the total set of knocked down pins is {1, 4, 5, 7, 8, 9}.
The complement of the knocked down pins would be the pins that were not knocked down. Therefore, the complement set is: {2, 3, 6, 10}.
Now we can evaluate the options:
Option #1: {3,4,6,9} - Contains 4 and 9, which are knocked down. Not a subset of the complement.
Option #2: {2,3,6,10} - All of these pins were not knocked down. This is the complement set.
Option #3: {1,4,5,7,8,9} - All of these pins were knocked down. Not a subset of the complement.
The correct answer is Option #2: {2,3,6,10}.