Exercise 4. Prove that The checkbook was on the breakfast, given the following premises (axioms) (i) If my checkbook is on my office table, then I paid my phone bill. (ii) I was looking at the phone bill for payment at breakfast or I was looking at the phone bill for (ii) If I was looking at the phone bill at breakfast, then the checkbook is on the breakfast tabl (iv) I didn't pay my phone bill. (v) If I was looking at the phone bill in my office, then the checkbook in on my office table. In order for you to discuss this exercise easily with other classmates, let's use following p: My checkbook in on my office table. q: I paid my phone bill. r: I was looking at the phone bill for payment at breakfast. s: I was looking at the phone bill for payment for payment in my office. t: The checkbook is on the breakfast table