Which of the following best explains a hardness scale?
A.
a scale that tests the hardness of a mineral by scratching other materials
B.
a scale that tests the hardness of a rock by scratching other materials
C.
a scale that tests the hardness of a mineral by being rubbed on other materials
D.
a scale that tests the hardness of a rock by being rubbed on other materials
1 answer
A. a scale that tests the hardness of a mineral by scratching other materials
1 answer