The daily sales of a retail store are normally distributed with a standard deviation of $500. If the probability that sales will be less than $10,000 in any one day is 40%, what are the mean daily sales?

Its one of these!

$9,873.35

$10,126.65

$12,533.65

None of the above

$12,553.65

9,873.35

$10,126.65

$12,533.65

$10,126.65

None of the above