Answer:
A. Air
Explanation:
A thermal insulator is a material that does not let the heat trasmitting through it, or it transmits heat not very efficiently.
Generally, the lower the density of the material, the better insulator the material is: this is because in materials with very low density, particles are very spread apart, so they cannot collide with each other, and so the vibrations of the particles (which determine how hot a substance is) cannot be transmitted very efficiently.
In the options listed in this problem, air is the material with lowest density, therefore it is the best thermal insulator among them.
Answer:
Newtons first law
Explanation:
Objects stay at rest until a force acts on it causing it to move from its resting position
Answer:5.13333333...
Explanation: 7.7 is the distance and an hour and a half is the average speed. You would have to divide the total distance by the total time. So it would be 7.7 divided by 1.5 which would equal 5.13333333333...
Explanation:
As per the problem,

When q > 0 then -q is a negative charge . Since, change in potential energy (
) increases.
or,
> 0
or, 
Therefore, both positive and negative charge will move from
to
and as
so both of them move through a negative potential difference.
Thus, we can conclude that the true statements are as follows.
- The positively charged object moves through a negative potential difference between A and B (that is, VB - VA < 0).
- The negatively charged object moves through a negative potential difference between A and B (that is, VB - VA < 0).