Chapter 3.7, Problem 17E

In Exercises 15-42, translate each argument into symbolic form. Then determine whether the argument is valid or invalid. You may use a truth table or, if applicable, compare the argument’s symbolic form to a standard valid or invalid form. (You can ignore differences in past, present, and future tense.)

There must be a dam or there is flooding.

This year there is flooding.

$\frac{\text{This}\text{year}\text{there}\text{is}\text{flooding}\text{.}}{\therefore \text{This}\text{year}\text{there}\text{is}\text{no}\text{dam}\text{.}}$