The challenges range from terrorism and violent extremism, to piracy, political instability, elections-related violence, drug trafficking or deadly viruses.
The picture is basically not necessary here, what the question is asking is : why do we have different time and different time zones?
Our time is divided into 24 hours, so you could ask: what happens every 24 hours? the answer is: the Earth rotates around its axis. So, the Earth motion responsible for this is its rotation around its axis.
I would say by using a telescope to look into the sky
"Theorem" is likely to be subject to be a direct geometric proof.
Answer:inertia and gravity
Explanation:
The factors which keep the Earth revolving around the sun are the inertia and the gravity. These forces work together in order to keep the Earth and moon in their respective orbits.