Center line
This is purely an opinion question. It's like asking which supermarket checkout line you should choose. You can choose any traffic lane you wish so long as it is not a marked HOV lane.
A closed system is designed to keep additional atoms from entering or exiting. An insulated system prevents heat from entering or exiting.
1/2 a mile.
Cell membranes
Yes
No.
Get on the brake ;)
If you miss the exit ramp
slow down quickly to safely merge into local traffic. Be prepared to check your surroundings, use your brake system effectively, and adjust your speed accordingly to smoothly transition from the expressway to the local road.
The vehicle exiting the parking space that did not yield to oncoming traffic.
No one. The air is toxic and out to get you. It's the government man.