URGENT! please show steps. finance chapter 14. always upvote!

Hollywood Shoes would like to maintain their cash account at a minimum level of $50,000, but expects the standard deviation in net dally cash flows to be $4.000, the effective anmual rate on marketable securities to be 6 percent per year, and the trading cost per sale or purchase of marketable securities to be $100 per transaction. What will be their optimal cash return point? Muliple Choice 554,00000 $1813166 $6958847 559.094.77