Potassium Content of Tomatoes. The size of the tomato you eat influences how much potassium you'll get from the vegetable. One large tomato contains 431 milligrams of potassium, which is almost 10 percent of your daily requirement. One medium-sized tomato supplies 292 milligrams of potassium and a small tomato provides 216 milligrams. A plum tomato or an Italian tomato each contains 147 milligrams of potassium.
The abacus, called Suan-Pan in Chinese, as it appears today, was first chronicled circa 1200 C.E. in China. The device was made of wood with metal re-inforcements. On each rod, the classic Chinese abacus has 2 beads on the upper deck and 5 on the lower deck; such an abacus is also referred to as a 2/5 abacus.
Chinese abacus appeared in Southern and Northern Dynasties (420 -580 A.D.) and was popular in the Song Dynasty and Yuan, was widely used in the Ming Dynasty. Chinese reckoning by abacus is orginated from ancinet way of chip counting in the West Zhou Dynasty.