During which period must snow fighter vehicles be serviced weekly?

The correct answer is that snow fighter vehicles must be serviced weekly from November 1 to April 15. This time frame encompasses the winter months when snowfall and icy conditions are most prevalent, making it crucial for snow fighting equipment to be fully operational and reliable. Regular servicing during this period ensures that the vehicles can effectively manage snow and ice, improving safety and minimizing disruptions to transit services.

In contrast, servicing during the other periods is less critical, as these months typically fall outside the peak winter weather conditions. Therefore, these times do not demand the same level of maintenance and readiness for snow fighter vehicles, which is why they are not designated for weekly servicing.