6. Rephrase in standard ”if.. then” form: ”In the United States, a good credit score is necessary for obtaining a loan.”
7. Rephrase in contrapositive form: ”If you are taller than 6 ft, then it is unpleasant for you to travel in economy class.” Your contrapositive must
not contain explicit references to negation. Assume that the negation of”unpleasant” is ”pleasant”.
8. Give a logically equivalent expression to ¬p→qthat does not use the conditional. Justify your answer.
9. Use De Morgan to given an equivalent statement of ”It’s not true that
Finley is rich and famous.”
10. Write the formal negation of∀x∃y(x > y). Your negation must not contain any explicit negation symbols.
11. Negate verbally: ”all people weigh at least 100 pounds.”