Final answer:
The correct answer is 1) 6380 km, which represents the radius of the Earth. This fact helps us understand Earth's position in the solar system as it revolves around the Sun, 150 million kilometers away. Earth orbits the Sun at a remarkable speed of about 110,000 kilometers per hour.
Step-by-step explanation:
The question asks about the radius of the Earth, which is a straightforward fact. The radius of the Earth is 6380 kilometers. Therefore, the correct answer to the question is option 1) 6380 km.
To expand on our understanding of Earth's relationship to the solar system, we know that Earth revolves around the Sun, which is about 150 million kilometers away. This distance is known as one astronomical unit (AU). It's fascinating to realize that light takes just over 8 minutes to travel 1 AU, so the sunlight we see took a little more than 8 minutes to reach us.
Moreover, Earth's motion in space is impressively fast. Despite the high velocity of about 110,000 kilometers per hour as Earth orbits the Sun, we do not sense this motion in our daily lives due to gravity keeping us anchored and the vacuum of space offering no resistance.