18 choose 7
=C(18,7)
=18!/(7!(18-7)!)
=31824
OR
18 choices for first passenger,
17 choices for second passenger,
....
12 choices for 7th passenger,
so total = 18*17*16...12
but there are 7! ways to order the 7 passengers, so
number of groups
=18*17*16...12/7!
=31824 as well
Answer:
D
Step-by-step explanation:
If it intersects the x axis, then y = 0. This is not possible, as you can plug in x to be 1/100000000000000000000000000000000000, or something very tiny, but it will never get 0. So, A is not a choice.
This also means B is not a choice.
If C is a choice, then it does not intercept the y axis, or x cannot be 0. This is not true, because (0, 1) is on the graph.
Finally, we have D. It intercepts the y axis (we have proven this in C). So, this is the only answer choice that is correct.