Tom puts $500$ into a savings account that pays an effective interest rate of $5\%$ for $10$ years, with interest credited at the end each year. If a withdrawal is made within the first seventy months then a penalty of $6\%$ of the withdrawal is applied. Tom withdraws K at the end of years $4,5,6$ and $7.$ The balance in the account at the end of year $10$ is $500.$ What is the balance at the end of year $5?$