Ok, if you roll the dice once - you'll get:
1, 2, 3, 4, 5 or 6.
If you roll it twice, you can get one of these combinations:
1,1 - 1,2 - 1,3 - 1,4 - 1,5 - 1,6
2,1 - 2,2 - 2,3 - 2,4 - 2,5 - 2,6
3,1 - 3,2 - 3,3 - 3,4 - 3,5 - 3,6
4,1 - 4,2 - 4,3 - 4,4 - 4,5 - 4,6
5,1 - 5,2 - 5,3 - 5,4 - 5,5 - 5,6
6,1 - 6,2 - 6,3 - 6,4 - 6,5 - 6,6
Here there are 36 combinations in total. Your chance of getting a 5 and a 2 is 1/36.
5,2 only appears once in this list of possible combinations. 2,5 doesn't count (as 2 would come up first).
Answer:
The prime factors of 15 are: 1,3,5,15
The prime factors of 21 are: 1,3,7,21
The prime factors of 38 are: 1,3,13,39
The prime factor of 42 is : 1,2,3,6,7,14,21,42
To find the circumference of a circle you can use either of these equations
3.14 X Diameter or 2 X 3.14 X Radius. But in this case we will use the first one. So 3.14 X 14 = 47.6 so the circumference of this circle would be 47.6 inches.
I hope this helps :)