A project's payback period is determined to be four years. If it is later discovered that additional cash inflows will be generated in years five and six, then: the project's payback period will be increased the project's payback period will be reduced the project's payback period will be unchanged the cost of capital must be known to determine whether the payback period will change two of the above choices (a) - (d) are correct none of the above choices (a) - (d) are correct