Find the expected value and standard deviation of the number of newspapers published in these large cities.

. The average number of dropouts for a school district has been 300 per year with a standard deviation of 50. What is the probability that the number of dropouts next year will be:   between 250 and 350?     between 300 and 350?

The commuting time for a student to travel from home to a university campus is Normally distributed with a mean of 45 minutes and a standard deviation of 10 minutes. If a student leaves home at 7 am, what is the probability that the student will arrive at the campus later than 8 am? A. 0.9332 B. 0.0668 C. 0.1409  D. 0.8956

Suppose that the average price for a gallon of gasoline in the United States is $3.77  and in Russia it is $3.38. Assume these averages are the population means in the two countries and that the probability distributions are normally distributed with a standard deviation of $0.25  in the United States and a standard deviation of $0.20  in Russia. a. What is the probability that a randomly selected gas station in the United States charges less than $3.60 per gallon (to 4 decimals)?   b. What percentage of the gas stations in Russia charge less than $3.60  per gallon (to 2 decimals)?   c. What is the probability that a randomly selected gas station in Russia charged more than the mean price in the United States (to 4 decimals)?