Final Answer:
After the first and second six-month period, only 3 passengers under the age of 21 who are NOT member of immediate family may ride in the vehicle.
Step-by-step explanation:
In this scenario, the restriction appears to limit the number of non-immediate family members under the age of 21 who can ride in the vehicle to three, following the completion of the first and second six-month periods. This likely pertains to regulations or conditions set for young drivers, potentially as part of a provisional or graduated licensing system.
These restrictions aim to minimize distractions or risks for newly licensed drivers by limiting the number of young passengers allowed in the vehicle during their initial months of driving. Such measures are often put in place to enhance road safety and minimize the chances of accidents, considering the increased risk factors associated with young, inexperienced drivers carrying a higher number of young passengers.
Correct answer: 3 and 21.