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.
The calculators that we use today are the advanced versions of a device that, when invented, was in its primitive form and was called the adding machine. Abacus. THE abacus wasnât a machine but a tool used for counting that was invented before 2000BC. Considered the basis on which the modern calculator has taken its shape, an abacus consisted of small ball-shaped beads that slid on sticks and the sticks were attached to a rectangular frame.