7. which of the following groupings lists only minerals?
a. obsidian, gypsum, corundum
quartz, coal, basalt
b. fluorite, feldspar, copper
d. pyrite, halite, brass

Your answer is A. The answer is not B or D because brass is not yet recognized as a mineral more of an alloy, and copper is a chemical element, so A must be the answer.

( PS: where is option choice C? )

Hope this helps, if not, comment below please

B which is Fluoritr, Feldspar and Copper.

Explanation:

Minerals are said to be solid substances which are usually present in nature but can also be formed from one or two substances.

Fluorite, which is also referred to as fluorspar, is a mineral that is comprised of calcium and fluoride or calcium fluoride.

Feldspars generally are a group of rock-forming tectosilicate minerals that make up about 41% of the Earth's continental crust by weight.

Copper is an element and mineral.

acceleration= v2-v1/t so 8m/s-3m/s / 3s =to 8/3 or

2.67 m/s^2

hope i

-lavira: )