Felix Industries purchased a grinder 5 years ago for $15,000. It is being depreciated on a straight-line basis over 15 years to an estimated salvage value of zero. It could be sold right now for $6,000. The firm is considering selling it and purchasing a new one. The new grinder would cost $25,000 installed and would be depreciated on a straight-line basis over 10 years to a zero estimated salvage value. The company's marginal tax rate is 40%. Determine the net investment if the old grinder is sole and the new one purchased. a. $19,000 b. $16,600 c. $17,400 d. $19,500