10.) (15 Points) Consider the following arguments. For each one, define the terms
needed in order to express them logically, and do so. Next, create a truth table, and
use it to show whether the argument is valid or invalid.
1.) Every time it rains, Bob's knee starts to hurt. One day, while sitting at his desk,
Bob starts complaining that his knee hurts. Obviously, that means it must be
raining outside.
2. You can ride the bus only if you have exact change. If you are in class, you took
the bus. That means that if you are in class, you had exact change.
3) May and Sid both work in the same office, but on different days. May is working
today, which means Sid is not.
4.) Carl will eat pizza or a sandwich tonight. If we order a pizza with mushrooms on
it, Carl won't eat it. Therefore, if we order a pizza without mushrooms, Carl will
have pizza tonight.
