(!! q => !p) => (p => !q)
Practice for the exam by solving the previous exams and homework problems from Prof. Ruiz's offerings of this course listed below. Solve the problems on your own before looking at the provided solutions. No need to submit your answers as part of your homework submission.
Some of the problems below use another textbook's notation in which a letter precedeed by "?" means that the letter is a variable (and not a constant)). For example, "?a" is a variable.