$.$ An automotive dealer borrowed $$9800\mathrm{.}00$ from the Bank of Montreal on a demand note on May $10.$ Interest on the loan, calculated on the daily balance, is charged to the dealer's current account on the $10$th of each month. The automotive dealer made a payment of $$2600$ on July $23,$ a payment of $$4200$ on October $1,$ and repaid the balance on December $1.$ The rate of interest on the loan on May $10$ was $7\%$ per annum. The rate was changed to $8\%$ on August $1$ and to $7\mathrm{.}5\%$ on October $1.$ What was the total interest cost for the loan? The total interest cost for the loan is $ $($Round the final answer to the nearest cent as needed. Round all intermediate values to six decimal places as needed.$)$