**Answer:**

The answer is C.

**Explanation:**

Graphite has a dull surface not transparent.

**Answer:**

This animal produces offspring that are genetically different from itself.

**Explanation:**

Answer:

13.687 grams of salt should be added

The total grams of 8.6% of brine solution produced is 852.687g

Explanation:

Solution mass= 962g

Salt= 6.2%

Water = 93.8%

962 gram of water is made up of:

902.356g ( due to vaporization which reduces mass)

= 902.356 - 123

= 779. 356g of water

59.644g of salt.

If we add x gram of salt for making brine solution up to 8.6%

=(59. 644g + x)g.of salt

% salt = Mass of Salt / Total mass of solution

= 0.086= 59.644 + x / 779.356 + 59.644 + x

= 59.644 + x / 839 + x

x= 13.687 g of salt

Grams of 8.6% brine solution will be:

Gram of water + total gram of salt added to form 8.6% brine solution.

= 779.356g +59.644g + 13.687g

= 852.687g

The total grams of 8.6% of brine solution produced is 852.687g

**Answer:**

4.2 x 10^24

**Explanation:**

6.9 mol C4H10 x (6.022 x 10^23 molecules / 1 mol) = 4.2 x 10^24

6.022 x 10^23 is Avogadro's number

It is a constant and applies to molecules, atoms, or particles of 1 mol of anything.