Please help with last question (d. The pretax return on capital)

Zif Software is a firm with significant research and development expenses. In the most recent year, Zif reported pretax operating income of $72M on $580M of capital, and the firm had $100M in R&D expenses. R&D expenses are amortizable over five years, and over the past five years they were: Assuming a linear amortization schedule (over five years), estimate: a. The value of the research asset. b. The total amount of R\&D amortization this year. c. The adjustment to operating income. d. The pretax return on capital