You can not use a person first name in second reference. Its to be full name mean surname
The answer is <span>tied to observable evidence
Theories that </span><span>tied to observable evidence had a solid measurement to be tested in order to prove whether those theories are right or wrong.
Without observable evidence, it would be closer to say that those scientific 'theories' are just personal opinion.</span>
Silk went westward, and wools, gold, and silver went east. China also received Nestorian Christianity and Buddhism (from India) via the Silk Road.
7.53 in 2017
But there are still more to come
Caste system
social institution
