Use the definition of the complement of an event to find the given probability.
1. A multiple-choice question has four possible answer choices (A, B, C, or D), one of which is correct. Suppose that an unprepared student does not read the question, but simply makes a random guess for the question. What is the probability that the student will guess incorrectly?
2. A box contains 30 identical-looking items of which 3 are defective. If one item is selected at random, what is the probability that the item is not defective?