Gold Miners in Alaska Have Found,on Average,12 Ounces of Gold

Multiple Choice

Gold miners in Alaska have found,on average,12 ounces of gold per 1000 tons of dirt excavated with a standard deviation of 3 ounces.Assume the amount of gold found per 1000 tons of dirt is normally distributed. What is the probability the miners find between 10 and 14 ounces of gold in the next 1000 tons of dirt excavated?

A) 0.2514
B) 0.4972
C) 0.5028
D) 0.7486