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20.31 Arco ships 15 million barrels of refined oil monthly from Arco-Canada to co-US. Arco-US. has to pay a US. ad valorem tariff of 6%. Tax accountants advise Arco that it can set the transfer price in the range of $15-$18 per barrel of product. The current price is set at $16 a barrel. If Arco-Canada's tax rate is 50% (the U.S. rate is 46%. what is the incremental cash fow per month associated with using the optimal transfer price? a) $236,000 b) $1,343,000 c) $1,086,000 d) $32,670