The annual salaries of employees in a large company are approximately normally distributed with a mean of $100,000 and a standard deviation of $10,000.

According to the above, what will the following be?

1. What is the probability that an employee earns a salary greater than $125,000?

2. What is the probability that an employee earns a salary less than $80,000?

3. The company provides free public transport to the employees that earn the lowest 10% of salaries. What salary does a person have to earn less than, to qualify for the free public transport?

4. A sample of 16 employees is now taken. What is the probability that the average annual salary of the 16 employees selected is less than $96,000?