Justify your answers and detail your calculations briefly. Answers should be brief and well described. Please check the file

Justify your answers and detail your calculations briefly.  

Answers should be brief and well described.

Please check the file 

Question 3:

The average price for a gallon of gasoline in the United States is $3.73 and in Russia it is $3.40 (Bloomberg Business week, March 5-March 11, 2012). Assume these averages are the population means in the two countries and that the probability distributions are normally distributed with a standard deviation of $.25 in the United States and a standard deviation of $.20 in Russia.

a. What is the probability that a randomly selected gas station in the United States charges less than $3.50 per gallon?

b. What percentage of the gas stations in Russia charge less than $3.50 per gallon?

What is the probability that a randomly selected gas station in Russia charged more than the mean price in the United States?

c. What is the probability that a randomly selected gas station in Russia charged more than the mean price in the United States?