When people take a mineral and hold it up, what kind of test is that? a) luster
b) cleavage
c) hardness
can someone plss help me??​

Luster

Explanation:

luster is the only answer that has to do with light. Luster is measured by the way a mineral reflects light.

Cleavage has to do with breaking minerals apart along certain fracture lines. Cleavage is not the answer.

Hardness is a test where one mineral is used to scratch another. The one that does the scratching is harder than the one that is scratched.  

hey, i believe your answer would be d. sugar ribose and the base uracil. i believe this is the answer, because rna consists of sugar ribose, adenine, guanine, cytosine, and uracil.

your first option is incorrect, because that's dna. where it consists of sugar deoxyribose, adenine, guanine, cytosine and thymine.

your second option is also incorrect, this is because sugar deoxyribose is in dna, and uracil is in rna. these two do not make sense together.

your third option being incorrect, because sugar ribose is in rna, but not the base of thymine. rna consists of uracil, not thymine.

lastly your fourth option being correct! this answer is correct, because both sugar ribose, and the base uracil are in rna! ~

answer is d. sugar ribose and the base uracil.