Mary buys 50 shares of XYZ stock for $80 per share. A year after, she sells the stock at $100 per share.

 (1) If she uses cash for this investment, what is the % return? 

(2) If she uses her margin account with a 60% margin, what is her % return? 

Now assume she sells at a loss at $60 per share,

(3) What is her % loss if it is a cash investment, and 

(4) What is her % loss if it is a margin investment with a 60% margin?

Please ignore all commissions and fees in this problem.