Julia plans to retire in $28$ years. She will make $336$ equal montly contributions to her retirement account. One month after her last contribution, she will begin the first of $180$ equal monthly withdrawals from the account. She expects to withdraw $$3000$ per month. How large must her monthly contributions be in order to accompish her goal if her account is assumed to earn interest at the APR of $3\mathrm{.}3\%,$ compounded monthly througout the life of this problem?

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