Answer:B
Explanation:
Given
speed of car 
mass of clump 
Radius of car tire 
Since the tire is rotating about axle so a centripetal force is acting constantly on each particle towards the center of tire.
Centripetal force is given by

where 



(inward)
Answer:
All materials are superconducting at temperatures near absolute zero kelvin.
Explanation:
All materials are superconducting at temperatures near absolute zero kelvin is false concerning superconductors.
Density =Mass/volume
When mass is constant, density is inversely proportional to volume or vice versa
When volume decreases, density increases
Hope it helps