I am taking a Statistics class this quarter, and I was wondering if anyone would be kind enough to help me figure out this problem? I am still learning, but I get lost pretty easily. I will be getting tutored sometime this week. Here it is:

A school system employs teachers at salaries between $30,000 and $60,000. The teachers' union and the school board are negotiating the form of next year's increase in the salary schedule. Supose that every teacher is given a flat $1000 raise.


a) How much will the mean salary increase? The median salary?

b) Will a flat $1000 raise increase the spread as measured by thed istance between the quartiles? Explain.

c) Will a flat $1000 raise increase the spread as measured by the standard deviation of the salaries? Explain.

Raising Pay: Suppose that the teachers in the previous question each recieve a 5% raise. The amount of the raise will vary from $1500 to $3000, depending on present salary. Will a 5% across-the-board raise increase the spread of the distribution as measured by the distance between the quartiles? Do you think it will increase the standard deviation? Explain.