EXERCISE 3.2.3: Proving arguments in English are valid using rules of inference. Prove that each argument is valid by replacing each proposition with a variable to obtain the form of the argument. Then use the rules of inference to prove that the form is valid. If I drive on the freeway, I will see the fire I will drive on the freeway or take surface streets (or both) I am not going to take surface streets. I will see the fire If it was not foggy or it didn't rain (or both), then the race was held and there was a trophy ceremony The trophy ceremony was not held .:. It rained (b) If I work out hard, then I am sore If I am sore,I take an aspirin I did not take an aspirin. .:. I did not work out hard Feedback