A person walks 4 m to the right and then turns around and walks 5 m to the left. What distance did they travel?
M

In the reading, yao chen-yuan describes traveling to deliver a message. why was he willing to risk danger to travelto tientsin? he wanted to the boxers with their cause

What type of matter is made of only one kind of atom

If many scientists conduct the same or similar experiments, and all obtain similar results, a can be written, which is a generally agreed-upon statement that explains and predicts how a natural phenomenon works.