The number of arrangements of 5 balls is 5! = 5 × 4 × 3 × 2 × 1 = 120.

The number of arrangements of 4 letters is 4! = 4 × 3 × 2 × 1 = 24.

The number of arrangements of the letters in 'SCHOOL' is 6! / 2! = 360.

The number of combinations of 10 toppings taken 4 at a time is C(10, 4) = 210.

The number of arrangements of 3 books is 3! = 3 × 2 × 1 = 6.

The number of arrangements of 5 books is 5! = 5 × 4 × 3 × 2 × 1 = 120.

The number of arrangements is 4! / 2! = 12, since 'O' repeats.

The number of ways to select 1 card from 52 is simply 52.

The number of combinations of 8 students taken 2 at a time is C(8, 2) = 8! / (2!(8-2)!) = 28.

The number of combinations of 3 students from 8 is C(8, 3) = 8! / (3!(8-3)!) = 56.

The total number of outfits is 4 shirts × 3 pants = 12.

The total number of outfits is 4 shirts × 3 pants = 12.

The number of combinations of 2 books from 5 is C(5, 2) = 5! / (2!(5-2)!) = 10.

The number of combinations of 6 books taken 2 at a time is C(6, 2) = 15.

The number of arrangements is 5! / (3!2!) = 10.

The number of combinations of 2 fruits from 5 is C(5, 2) = 5! / (2!(5-2)!) = 10.

The number of combinations of 10 fruits taken 3 at a time is C(10, 3) = 10! / (3!(10-3)!) = 120.

The number of combinations of 4 toppings from 10 is C(10, 4) = 10! / (4!(10-4)!) = 210.