Answer:
competitive advantage
Explanation:
Based on the information provided within the question it seems that in this scenario Mainline Ltd. has a competitive advantage. This term refers to when a company or business has a certain condition or circumstance that allows it to outperform it's competitors within the market. Which is what Mainline Ltd. must have in order to average 2 percent ROI in an industry who's average ROI is -5 percent.
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