(a) A store sells 8 colors of balloons with at least 28 of each color. How many different combinations of 28 balloons can be chosen? Apply the method of Example 9.6.2 using balloons instead of cans of soft drinks to find that the number of different combinations of 28 balloons that can be chosen is (b) If the store has only 12 red balloons but at least 28 of each other color of balloon, how many combinations of balloons can be chosen? Use the method of Example 9.6.2(c) to answer this question. If the store has only 12 red balloons, then the number of different selections of 28 balloons of the different colors is the same as the number of different selections that contain 12 or fewer red balloons. Let 7 be the set of all possible selections, assuming that there are at least 28 balloons of each type, let R ≤12 be the set of selections in 7 that contain 12 or fewer red balloons, and let R≥13 be the set of selections from 7 that contain 13 or more red balloons. Use the relationships among R≤12, R≥13, and 7 to find that the number of different combinations of 28 balloons that can be chosen is (c) If the store has only 8 blue balloons but at least 28 of each other color of balloon, how many combinations of balloons can be chosen? (d) If the store has only 12 red balloons and only 8 blue balloons but at least 28 of each other color of balloon, how many combinations of balloons can be chosen?