The correct answer is 2 over 12 because you can simplify it
Well you could do 5(60x+20y), 100(3x+y), and 2(150x+50y)
I believe your answer is going to be increasing linear. If it's doubling constantly then it's increasing so that takes out 2 options. And since it's constant, it isn't exponential, therefore you only have increasing linear left.
I hope I was able to help. Best of luck.
Answer:
3m I believe I'm not fully sure