Caleb is playing a word game with his father who likes to make up random words. if caleb's father only makes up six letter words that have 2 vowels and no repeating letters, how many possible words can he make on a turn? a. 26 × 6 = 156 b. 21 × 20 × 19 × 18 × 5 × 4 = 2,872,800 c. 6 × 21 × 20 × 19 × 18 × 5 × 4 = 2,872,800 d. 26 × 26 × 26 × 26 × 26 × 26 = 308,915,776