Contour intervals between contour lines
To perform this test to check if gold is real, make a light, tiny scratch on the item using a small nail file. Choose a spot that is not noticeable if possible. Use a dropper to apply a small drop of nitric acid to the scratch. If there is no reaction, then the piece is probably made from real gold.
Answer: did you try using goog
Explanation:
And instead of use the arrow use a equal sign
I would say true. I say this because there have been times where scientists find out that there are better ways of performing experiments, or found that certain materials work better for certain tasks. (Especially true in medicinal fields!)
