In order to make vehicles more energy efficient, what can be done?

a. improve fuel standards; more miles per gallon
b. improve engine design
c. reduce the weight of the car
d. all of the above

I’d say D. All of the above, but I’m not particularly knowledgeable about this, so I could be wrong.

the aurora is formed when charged particles emitted from the sun during a solar flare penetrate the earth's magnetic shield and collide with atoms and molecules in our atmosphere. these collisions result in countless little bursts of light, called photons, which make up the aurora.

auroras are generated by charged solar particles hitting molecules in earth's atmosphere. this usually happens in high latitudes, because our planet’s magnetic field tends to funnel these particles toward the poles. that’s why it can be experienced in northern ohio.

1 is a answer of a question