A barrel of oil weighs 40 kg. I used 13 for the first time. I used the remaining 35 for the second time. What percentage of the barrel of oil was used for the second time? How many kilos are left?

A barrel of oil weighs 40 kg. I used 13 for the first time. I used the remaining 35 for the second time. What percentage of the barrel of oil was used for the second time? How many kilos are left?

A piece of iron wire is 5 meters long and cut into 6 sections on average. Each section is a few tenths of a meter long, each section is 5 meters long and each section is a few tenths of a meter long, which is equivalent to a few tenths of a meter long

A piece of iron wire is 5 meters long and cut into 6 sections on average. Each section is 5 / 6 of the length of 5 meters, which is equivalent to 5 / 6 of 1 meter

How many parts of a meter is a nanometer?

Nanometer (nm) is a unit of length, originally known as nanometer, which is 10 ^ - 9 meters (one billionth of a meter), that is 10 ^ - 6 mm (one millionth of a millimeter). Like centimeter, decimeter and meter, it is a unit of length measurement. It is equivalent to four times the size of an atom, smaller than the length of a single bacterium. A single bacterium is invisible to the naked eye, and its diameter measured by microscope is about five microns