It is possible to obtain a quick and dirty estimate of the mean of a normal distribution

Question:

It is possible to obtain a “quick and dirty” estimate of the mean of a normal from the fiftieth percentile value on a normal probability plot. Provide an argument why this is so. It is also possible to obtain an estimate of the standard deviation of a normal by subtracting the sixty-fourth percentile value from the fiftieth percentile value. Provide an argument why this is so.
Distribution
The word "distribution" has several meanings in the financial world, most of them pertaining to the payment of assets from a fund, account, or individual security to an investor or beneficiary. Retirement account distributions are among the most...