Answer:
1. False
2. True
3. True
Explanation:
1- False —> The relation between electric potential and electric field is given such that

Therefore, for a uniform E field, electric potential is linearly proportional to the distance.
2- True —> The electric field lines always cross the equipotential lines perpendicularly.
3- True —> In order to be a potential difference, one source of electric field is enough. The electric potential will decrease radially according to the following formula:

There is no test charge in the formula, only the source charge. Even when there is no test charge, the potential difference between points in space can exist.
Sound Waves will be an example of mechanical waves.. hope this helps!
Answer:
B. The same on the moon.
Explanation:
The density of an object is the ratio of the mass contained by the object to the volume occupied by that mass.

When the object is taken from the earth to anywhere in the universe, its mass remains constant. The dimensions of the object and hence its volume also remains constant anywhere in the universe.
Therefore, the density of the object will also remain the same as it depends upon the mass and the volume of the object.
So, the correct option is:
<u>B. The same on the moon.</u>