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.
In general, cell phones do not use a dial tone. If the phone is off, then the user knows it is not in use since there is only one âlineâ per phone. The number can be dialed ahead of time, and the âsendâ button pressed.