Do you currently have car insurance? Insurance is mandatory to drive in California Yes I have insurance. But please show me your best quotes. No, please help me find the best insurance. Question How many daily hours of sleep does an adult need to maintain alertness? Answers Six to seven Seven to eight Eight to nine Four to five Explanation Being properly rested is essential to the safe operation of a CMV. To maintain alertness, most people need eight to nine hours of sleep per night. Take a FREE Practice Test Now This questions appears in the following tests: Wisconsin Knowledge Test Class B ,