Final answer:
A bus driver is typically required to have at least 10 consecutive hours off-duty per day according to FMCSA regulations. A union's ability to negotiate higher wages can lead to an excess supply of workers in the labor market. The probability of waiting under 12.5 minutes for a bus, with wait times uniformly distributed up to 15 minutes, is approximately 83.33%.
Step-by-step explanation:
A bus driver must have a certain number of off-duty hours per day to ensure they are well-rested and can operate the vehicle safely. The correct answer is not provided in the options above. However, according to the U.S. Department of Transportation's Federal Motor Carrier Safety Administration (FMCSA) regulations, which likely influence how this sort of question would be approached in the United States, property-carrying drivers are required to take at least 10 consecutive hours off-duty.
In terms of economics, for a fully operational bus route system without a union, the equilibrium wage rate might be determined by the balance between supply and demand in the labor market. If a union is powerful enough to negotiate a higher wage, this could lead to an imbalance, causing an excess supply of labor. For example, if the wage increases from $18 to $22 per hour, there might be more workers willing to supply their labor (10,000) than there is demand for it (4,000), resulting in an excess supply of 6,000 workers.
Concerning probabilities, if the waiting time for a bus is uniformly distributed between zero and 15 minutes, the probability of a person waiting fewer than 12.5 minutes for a bus would be the number of minutes less than 12.5 over the total range of minutes, which is calculated by the fraction (12.5 minutes / 15 minutes) giving us roughly an 83.33% chance of waiting less than 12.5 minutes.