How did the roman empire and chinese Dynasty understand each other around the year 200 AD

where is the passage

i cant solve it without knowing the passage

rescuing someone who is in danger. hope this : )

copernicus finished the first manuscript of his book, "de revolutionibus orbium coelestium" ("on the revolutions of the heavenly spheres") in 1532. in it, copernicus established that the planets orbited the sun rather than the earth. he laid out his model of the solar system and the path of the planets.