How large is the Earth?
The Earth's radius is 6378 kilometers, and its mass is 5.972 x 10^24 kilograms. Its surface area is about 510 million square kilometers.
Instruction: How large is the Earth?
Context: 
Response: The Earth's radius is 6378 kilometers, and its mass is 5.972 x 10^24 kilograms. Its surface area is about 510 million square kilometers.