Question: 1. A person is murdered at twilight near the outskirts of a town of population 5,000, in view of several witnesses. The dastardly murderer has been described as male, between the ages of 16 and 35, with glasses, and under 6 feet tall. The police search Department of Motor Vehicles records for the city in an effort to narrow down the identity of the criminal.
Let F indicate that the driver is female, let O indicate that the driver is over the age of 35, let E indicate that the driver is not required to wear corrective lenses, and let T indicate that the driver is over 6 feet tall.
The police obtain the following data:
In a discussion of these data, the police chief says the murderer doesn't reside in the city. A detective responds by saying that the DMV records are incorrect. Why does each crime-fighting official make the claim that s/he does?
2. How many passwords can be constructed that have between 6 and 12 characters, and must use at least one letter and at least one number (and no special characters) but are not case sensitive?