To calibrate the scale.
You do 375 * 14.25% and get 53.4375, rounded to the nearest hundreds is 53.44 pounds.
yes you can use nickel on a ball mill yes you can use nickel on a ball mill
You use the scales.
If you were to calculate the mass of a nickel you would use grams or milligrams if you were to measure the diameter of a nickel you would use millimeters.
Weighing things.
a weighing scale
a scale. A US nickel weighs exactly 5 grams.
weighing scale
Kodak use Nickel-titanium or stainless steel film for x rays.
Very carefully
Citric acid is safe to use on most things you could name, nickel included.
Chances are it is worth something. The question though is, was it a nickel struck on a quarter blank? Or was the nickel simply struck off-center? If it was struck on a quarter blank, the edge will have both redish brown and white. If it was struck on a nickel blank it will be a solid color. The best thing to do is take it in to several coin shops and get different opinions on what its worth. It is hard to give values for error coins sight unseen. But some coin dealers specialize in errors while others use them simply for curiosities.