3. The average number of calories in a 1.8-ounce chocolate bar is 230. Suppose that the distribution of calories is approximately normal with a standard deviation of 10. Find the probability that a randomly selected chocolate bar will have less than 200 calories 4 The average monthly salary of 500 teachers of Candelaria East district is P26,500 If the monthly salaries of the teachers are normally distributed with standard deviation of P2,500, approximately how many teachers in the district are earning more than P30,000 monthly?​