Why An Underground Mine Might Be Better For Local Ecosystem Than A Surface Mine?

Surface mining is suitable for large, low-grade ore deposits which occur below a thin layer of rock or sand. Underground mining is used for small, high-grade deposits covered with a thick soil or rock above the ore. Alluvial mining is suitable for deposits in sand and riverbeds.

Explanation:

Environmental impacts of mining can occur at local, regional, and global scales through direct and indirect mining practices. Impacts can result in erosion, sinkholes, loss of biodiversity, or the contamination of soil, groundwater, and surface water by the chemicals emitted from mining processes.

answer: 21

step-by-step explanation:

divide 630 by 30. 30 goes into 630 21 times

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.