Answer:
The star-sphere discovered by the Greeks and other ancient civilizations which shows the physical location in space of the nearby stars.
Explanation:
The celestial sphere is an ideal sphere, without defined radius, concentric with the terrestrial globe, in which the stars apparently move. Some ancient civilizations such as the Greeks assumed that the stars were attached to a celestial sphere, which revolves around the earth, while our planet is always immobile.
It is required an infinite work. The additional electron will never reach the origin.
In fact, assuming the additional electron is coming from the positive direction, as it approaches x=+1.00 m it will become closer and closer to the electron located at x=+1.00 m. However, the electrostatic force between the two electrons (which is repulsive) will become infinite when the second electron reaches x=+1.00 m, because the distance d between the two electrons is zero:

So, in order for the additional electron to cross this point, it is required an infinite amount of work, which is impossible.
Answer:
made with the material that is water proof
Answer:
Option (C)
Explanation:
Flash flood refers to the sudden flood that occurs in a particular area due to the heavy and excessive amount of rainfall, often accompanied by thunderstorms within a few hours. It releases a huge amount of water due to the failure of natural levee as well dam. They are very devastating. During flash flood, the water exerts a massive force which can make vehicles float over water. The <u>six inches of water</u> that flows over an area has the capacity to lift the tyres of small vehicles and carry hem further away.
Thus, the correct answer is option (C).