Clearlake Optical has a $50,000 note that comes due in 6 years. The owners wish to create a sinking fund to pay this note. If the fund earns 3.5% compounded semiannually, how much must each semiannual deposit be? (Round your answer to the nearest cent.)

Assuming the payments are at the end of each half-year ...

i = .035/2 = .0175
n = 12
pay = ?

pay( 1.0175^12 - 1)/.0175 = 50000
solve for 'pay'