shang dynasty
because the existence of the Xia dynasty is debated, the shang dynasty is sometimes seen as the first of chains dynasty.The shang rurals maintained control for about 600 years. The period of the rule saw the invention of Chinese writing and may later historians viewed it as china's 'Golden Age'. In 1046 B.C.E.
The inhalation of mercury vapor can produce harmful effects on the nervous, digestive and immune systems, lungs and kidneys, and may be fatal. Mild, sub-clinical signs of central nervous system toxicity can be seen in workers exposed to an elemental mercury level in the air of 20 μg/m3 or more for several years.
Convert to Hz from MHz: 88.9 MHz x 1x106Hz /1MHz = 8.89x107 <span>Hz </span>
i thnk the answer is A ...........................
