The answer I got is $11,520 each year. Please let me know if this is right. Also show it on excel

Your friend would like your assistance in determining how much to save for retirement. He is planning to invest $ 10,000 in a tax-sheltered retirement fund at the end of each year (i.e., appreciation of the fund is not taxed). The rate of return each year can be modeled as a normally distributed random variable with a mean of 12 percent and a standard deviation of 2 percent and can vary from year to year. He is 45 years old now. 1. How much should he invest each year if he wants the mean value of his portfolio to be at least $ 500,000 at age 60? Please show the data or chart to support your argument