Correct Answer: C. Coal

Correct Answer: C. 644 A.D

Correct Answer: B. FKMY996532AEU

Explanation

To rearrange the given string 2F39EAUYMK596 according to the instructions:

1. Consonants in alphabetical order:

* Consonants present: F, Y, M, K

* Alphabetical order: F, K, M, Y

2. Numbers in descending numerical order:

* Numbers present: 2, 3, 9, 5, 9, 6

* Descending order: 9, 9, 6, 5, 3, 2

3. Vowels in alphabetical order:

* Vowels present: E, A, U

* Alphabetical order: A, E, U

Putting them all together: FKMY996532AEU

Therefore, the correct answer is B. FKMY996532AEU.

Correct Answer: B. 13.2°C

Correct Answer: A. wriggler

Correct Answer: A. entrap Him in His talk

Correct Answer: A. a contract between the rulers and the ruled

Explanation

Modern democracy in many ways is the opposite of ancient democracy. Modern democracy requires that there must be a constitution, that there must be equality before the law, there must be individual rights and liberties, there must be civil rights and liberties, there must be human rights and there must be the rule of law to enforce those rights and liberties. In modern democracy, governance is a contract between the citizens and the ruled. This means that, the citizens choose people who would represent them (usually through elections) at various levels for a particular period of time, and these representatives are accountable to the people.

Correct Answer: C. promoting economic integration

Correct Answer: B)

Ca(NO\(_3\))\(_2\) + 2H\(_2\)O

Explanation

The given reaction is between nitric acid (HNO\(_3\) and calcium hydroxide (Ca(OH)\(_2\). This is an example of an acid-base reaction, where an acid reacts with a base to form a salt and water. In this case, the acid is HNO\(_3\) and the base is Ca(OH)\(_2\).

When reacting, the hydrogen ions (H\(^+\) from the acid combine with the hydroxide ions (OH\(^-\) from the base to form water (H\(_2\)O). The remaining ions, calcium (Ca\(^{2+}\) and nitrate (NO\(_3^-\), combine to form the salt calcium nitrate (Ca(NO\(_3\)\(_2\).

So, the balanced chemical equation for the reaction is:

HNO\(_3\) + Ca(OH)\(_2\) \(\rightarrow\) Ca(NO\(_3\)\(_2\) + 2H\(_2\)O

Therefore, the correct answer is Option B: Ca(NO\(_3\)\(_2\) + 2H\(_2\)O.

Explanation

(a) \(\sqrt{\frac{0.18 \times 12.5}{0.05 \times 0.2}}\)

\(\frac{0.18 \times 12.5}{0.05 \times 0.2} = \frac{18 \times 10^{-2} \times 125 \times 10^{-1}}{5 \times 10^{-2} \times 2 \times 10^{-1}}\)

= \(9 \times 25 \times 10^{-3 - (-3)}\)

= \(9 \times 25\)

= \(225\)

\(\therefore \sqrt{\frac{0.18 \times 12.5}{0.05 \times 0.2}} = \sqrt{225}\)

= \(15\).

(b) \(\frac{8 - 4\sqrt{18}}{\sqrt{50}}\)

\(\sqrt{18} = \sqrt{9 \times 2} = 3\sqrt{2}\)

\(\sqrt{50} = \sqrt{25 \times 2} = 5\sqrt{2}\)

\(\frac{8 - 4(3\sqrt{2})}{5\sqrt{2}} = \frac{8 - 12\sqrt{2}}{5\sqrt{2}}\)

Rationalising, we have

= \(\frac{8 - 12\sqrt{2}}{5\sqrt{2}} \times \frac{\sqrt{2}}{\sqrt{2}}\)

= \(\frac{8\sqrt{2} - 24}{10}\)

= \(0.8\sqrt{2} - 2.4\)

= \(-2.4 + 0.8\sqrt{2}\)

(c) \(x \propto \frac{y^{3}}{z^{2}}\)

\(\implies x = \frac{ky^{3}}{z^{2}}\)

\(108 = \frac{k \times 3^{3}}{4^{2}}\)

\(k = \frac{108 \times 16}{27}\)

\(k = 64\)

\(\therefore x = \frac{64y^{3}}{z^{2}}\)

\(\therefore 4000 = \frac{64 \times 10^{3}}{z^{2}}\)

\(4 = \frac{64}{z^{2}}\)

\(z^{2} = \frac{64}{4} = 16\)

\(z = \sqrt{16} = \pm 4\)