4. Elzbieta sells vacuum cleaners door to door, and finds that she has a 10% chance of being invited in to demonstrate the vacuum cleaner. If she is invited inside for the demonstration, she usually sells a machine in 12% of the households. However, if she is not invited in, she makes a sale in only 2% of the households. What is the probability that she makes a sale?

5. Two dice are rolled. What is the probability that the first die shows a 3 or the second die shows an even number?