Answer:
See attached picture to view the graph
Step-by-step explanation:
Start by analyzing how this average idea works:
If only one member goes to the trip, it will cost him/her $1000+$200 = $1200.
If two members go to the trip, then they will share the cost as per the following: ($1000+ $200 + $200 = $1400) which they will be dividing into two people, thus costing each of them $700.
Notice that the general function that represents such average will be given by: 
Plot such function in the two dimensional plane, and you will get the asymptotic behavior shown in the attached image.
The answer is B.
14 + 15x
14 + 15(5)
14 + 75
89
Before going to B.two-digit addition
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