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.
It is unknown when exactly were developed first devices to facilitate calculation, such as the counting board, or abacus. The counting board was invented when someone grasped the idea of placing pebbles or other objects in columns marked on a flat surface, and assigning an order of units to the objects in each column.ater, loose objects in columns were replaced with beads that could slide along parallel rods. There is an unproved information, that similar to abacus device was used in Babylonia as early as 2400 BC. The word abacus itself is a Latin word, which comes from Greek Î¬Î²Î±ÎºÎ±Ï (board or table).