Which of the following are relevant cash flows in the evaluation of a proposal to produce a new product?

a. Decrease in the cash flows of a substitute product.

b. Alternative of leasing an existing building that will be used for manufacturing this product.

c. The cost of a new machine required to produce this product.

d. Salvage value of the new machine at the end of its useful life.

e. Increase in net working capital at the beginning of the project’s life.

f. Cost to develop a product prototype last year.