2018
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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130 years
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125 years
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165 years
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175 years
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Detailed explanation-1: -The kilogram is now defined in terms of the Planck constant, h, which has been measured with extraordinary precision in recent years. Its agreed value will be set as 6.626,070,15 × 10-34 kg m2 s–1, with researchers able to make precise mass measurement using equipment such as the Kibble balance.
Detailed explanation-2: -For more than a century, the kilogram (kg) - the fundamental unit of mass in the International System of Units (SI) - was defined as exactly equal to the mass of a small polished cylinder, cast in 1879 of platinum and iridium.
Detailed explanation-3: -kilogram (kg), basic unit of mass in the metric system. A kilogram is very nearly equal (it was originally intended to be exactly equal) to the mass of 1,000 cubic cm of water. The pound is defined as equal to 0.45359237 kg, exactly.