With an initial investment of $1000, I will add $100/month for the first year, and $200/month for

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With an initial investment of $1000, I will add $100/month for the first year, and $200/month for 4 years after that. The nominal interest rate is 6% p.a. and is compounded monthly. If I stop investing in this account but leave the money in at the same interest rate, how much money will I have in 40 years when I retire?