i need the answer to this

Merry's Berries makes three products from a common input. These products and their selling prices are as follows: Simplex, $5.00 per lb; Duplex, $7.50 per lb; and Triplex, $10.00 per lb. Using 100,000lbs of the input, Merry was able to produce 60,000lbs of Simplex, 20,000 lbs of Duplex and 20,000lbs of Triplex. The costs incurred after the split-off point were: Simplex, $75,000; Duplex, $60,000; and Triplex, $115,000. The 100,000lbs of input cost $80,000. If the net realizable value method is used to allocate joint costs, the joint cost allocated to Duplex will be: a) $14,000 b) $16,000 c) $18,000 d) $20,000