C, velocity I believe this is the answer to your question
Answer:
You are exactly right. The molecules in hot air are moving faster than the molecules in cold air. Because of this, the molecules in hot air tend to be further apart on average, giving hot air a lower density. That means, for the same volume of air, hot air has fewer molecules and so it weighs less
A concave mirror is curved inward in the middle, more
like a cave. Because the mirror is curved inward, the angle of the light
surface can be focused similar to that of the camera. They can form real images
that are projected out in front of the mirror at the place where light focuses.
When the object is located at the center of the curvature the image formed will
also be at the curvature. The image will be inverted and the magnification
value is equal to 1 which will become a real image because the ray of light
converges at the location of the formed image.