Answer: a rate commensurate with the risk level of the project.
Step-by-step explanation:
When computing the net present value of the new project, we should note that the cash flows should be discounted using a rate that is commensurate with the risk level of the project.
Since it is a new project and it possesses risks that are unrelated to those of the current firm's product, the risk that pertains to the project level should be used in the discounting to get the net present value.