21 millimeters is approximately 0.83 inches in the U.S. measurement system. To convert millimeters to inches, you can divide the number of millimeters by 25.4, as there are 25.4 millimeters in an inch. Therefore, 21 mm is just under one inch.
A 21mm measurement is roughly equivalent to the diameter of a small coin, such as a quarter or a large button. In terms of visual size, it is about the width of a standard paperclip or slightly larger than the size of a typical fingernail. In photography, a 21mm lens would provide a wide-angle view, capturing more of the scene than a standard lens. Overall, 21mm is a compact size that can be easily conceptualized with everyday objects.
the smallest measurement in the us
21mm
346.36 square MM.
Because you haven't told us what the measurement is.
12x1.5 or 21mm 12x1.5 or 21mm
0.021m
the smallest measurement in the us
21mm
21MM
27mm x 21mm
21mm
2.1 cm 10mm = 1cm
21mm
346.36 square MM.
Use the formula: V= 4/3*pi*r^3 I would convert 21mm to metres straight away. 21mm=0.021m Then apply the formula and you get Vol=0.000038792m^2 to 10 sig figures
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