Share to: /   The Chinese make light Work of Payment: The Invention of Paper Money   / Around 650 AD, the emperor of China began to issue paper value tokens for general use.
Answer: No. Mobile phones do not give off sub-atomic (ionizing)  radiation.    Answer: Yes. Mobile phones emit microwave (millimeter to  centimeter range) electro-mag â¦ netic radiation, mostly at frequencies  from 800 to 1800 MHz (1.8 GHz).This is below infrared.nswer: No. Mobile phones do not give off sub-atomic (ionizing)  radiation.    Answer: Yes. Mobile phones emit microwave (millimeter to  centimeter range) electro-mag â¦ netic radiation, mostly at frequencies  from 800 to 1800 MHz (1.8 GHz). This is below infrared.
A busy signal is a signal that indicates that the telephone number someone is trying to call cannot be reached because the phone is otherwise engaged, or because the circuits are busy, making the call impossible to complete.