D
7•4 =28, -5•0 =0... 28+0=28
B. f(x)=5(6.86x) this the correct anwser
The total number of arrangements for all of them to be women is:
C(7, 4) because the order does not matter; we'd still have the same arrangements.
Now, we can simplify this:




Now, the total number of arrangements, without restriction, is simply: C(12, 4) because we don't care who we pick.