If a company's required rate of return is 10% and, in using the net present value method, a project's net present value is zero, this indicates that the

The project earns a 10% rate of return

Explanation:

This indicates that the “ project earns a 10% rate of return”. Since it is given in the question that the required rate of return is 10% and the company analysis that the net present value of the project is zero. That means the project is profitable and earns a sufficient profit or project giving a sufficient return. Therefore, it can be determined that the project is providing the earning or rate of return 10 per cent.  

b. take periodic breaks and alternate between tasks.  

will increase work efficiency, and avoid health issues.