"n choose k" gives you the number of possible unique combinations...
n!/(k!(n-k)!)
n=number of elements to choose from and k=the number of elements that you choose...in this case:
7!/[2!(7-2)!]
7!/[2!5!]
21
There are 21 possible different two question combinations that she can pick.
It is equal to 4.0071221 ounces
Since you're adding x feet to the length which is 12 feet:
New area: (12+x)10.5
6t + 5j= 34
2t + 3j = 16
12t + 10 j = 68
12t + 18j = 96
-8j = -28
j = 3.5
jelly beans= 3.5 and trail mix = 2.75