HWK2_Zhangy

Please name your file as your last name + first letter of your first name+_HWK2.  If you fail to do it, you will lose 5% of the homework grade for this assignment.  For example, my file is zhangy_HWK2
Only turn in excel file.  If you need to answer questions, please do that in the excel file too.  Please number the problems and part a, b, c, etc clearly.  For example, problem 1, will be numbered as 1a), 1b)….etc.