6. In a recent month, 88% of automobile drivers filled their vehicles with regular gasoline, 2% purchased midgrade gas, and 10% bought premium gas. Of those who bought regular gas, 28% paid with a credit card; of customers who bought midgrade and premium gas, 34% and 42%, respectively, paid with a credit card. Suppose we select a customer at random. What's the probability that the customer paid with a credit card? Make a tree diagram for one adult to illustrate this probability model. Use line 118 to simulate 10 trials, then record your experimental probability