Chang Corporation issued $6,000,000 of 9%, ten-year convertible bonds on July 1, 2020 at 104 plus accrued interest. The bonds were dated April 1, 2020 with interest payable April 1 and October 1. Bond premium is amortized semiannually on a straight-line basis. On April 1, 2021, $1,200,000 of these bonds were converted into 500 shares of $20 par value common stock. Accrued interest was paid in cash at the time of conversion.

If "interest payable" were credited when the bonds were issued, what should be the amount of the debit to "interest expense" on October 1, 2020?

$129,000

$135,000

$141,000

$270,000