You can write in any topic direction, as long as there is some innovation. For many people, innovation is not an absolute subversion. For example, studying an original problem based on a new perspective, a new environment and a new method is also innovation. Try to avoid blindly pursuing tall, novel and even unfamiliar topics. It is the most important thing to be able to write it.

Here, let's take the profit problem as an example. I hope you can draw inferences and find other novelty points.

Return on equity (ROE) is the most direct indicator to measure profitability. According to DuPont's formula analysis; Return on net assets = net profit rate of sales * asset turnover rate * equity multiplier.