if you are totally sure then attempt other wise skip this is third time I'm posting previously two time got incorrect Answer i.e($871)

if your ans is incorrect then I will give many Thumbs down

Question: You paid $10000 to buy a 10-year bond with a face value of $10000. How much is your expected lost or gain if you sell it in 6 years? The bond has a coupon rate of 6.4% compounded semi-annually. The bond is sold to yield 7.4% compound semi annually. Correct Answer is $340.85

please give me equation on how to solve.