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The uses of graphite: Used in making a pencil. Used as a dry lubricant. For making electrodes. For polishing iron articles. As a moderator in the nuclear furnace. The moderator of a nuclear reactor is a substance that slows neutrons down.

The ciliary body produces the fluid in the eye called aqueous humor. It also contains the ciliary muscle, which changes the shape of the lens when your eyes focus on a near object. This process is called accommodation.

Bronze is a mixture of copper and tin. Water is a compound of the elements hydrogen and oxygen.

In the reaction NH\(_3\) + H\(_3\)O\(^+\), H\(_3\)O\(^+\) acts as an acid, donating a proton (H\(^+\)) to NH\(_3\), which then becomes NH\(_4\)\(^+\). According to Brønsted-Lowry Acid-Base Theory, an acid is a substance that donates a proton (H\(^+\)), while a base is a substance that accepts a proton. H\(_3\)O\(^+\) (Hydronium Ion) is formed when a proton (H\(^+\)) is added to a water molecule (H\(_2\)O.). In the reaction NH\(_3\) + H\(_3\)O\(^+\) → NH\(_4\)\(^+\) + H\(_2\)O, H\(_3\)O\(^+\) donates a proton (H\(^+\)) to NH\(_3\), forming NH\(_4\)\(^+\) and H\(_2\)O.

The incomplete combustion process that occurs in an engine; result to the emission of carbon monoxide (CO) as a waste product from the exhaust system of vehicles. Environmental carbon monoxide is produced by incomplete combustion process from any carbon containing fuel.

S = {1, 2, 3, 4, 5, 6}; T = {2, 4, 5, 7}; R = {1, 4, 5} (S∩T) ∪ R = {2, 4, 5} ∪ {1, 4, 5} = {1, 2, 4, 5}

\(\frac{3}{4} \div 1\frac{1}{4} \times (1\frac{1}{2} - \frac{2}{3})\) \(\frac{3}{4} \div \frac{5}{4} \times (\frac{9 - 4}{6})\) = \(\frac{3}{4} \times \frac{4}{5} \times \frac{5}{6}\) = \(\frac{1}{2}\)

3m + 3 > 9 3m > 9 - 3 3m > 6 m > 2

\(89_{10}\) 2 89 2 44 r 1 2 22 r 0 2 11 r 0 2 5 r 1 2 2 r 1 2 1 r 0 0 r 1 \(89_{10} = 1011001_{2}\)

% error = \(\frac{error value}{true value}\) x 100% % error = \(\frac{1.80 - 1.75}{1.75}\) x 100% = \(\frac{0.05}{1.75}\) x 100% = \(\frac{20}{7}\)% = 2\(\frac{6}{7}\)%

\(\frac{4^{-\frac{1}{2}} \times 16^{\frac{3}{4}}}{4^{\frac{1}{2}}}\) = \(\frac{16^{\frac{3}{4}}}{4^{\frac{1}{2}} \times 4^{\frac{1}{2}}}\) = \(\frac{(2^4)^{\frac{3}{4}}}{4^{\frac{1}{2}} \times 4^{\frac{1}{2}}}\) = \(\frac{2^3}{4}\) = 2

\(\frac{\log \sqrt{27}}{\log 81}\) = \(\frac{\log \sqrt{3^3}}{\log 3^4}\) = \(\frac{\log 3^{\frac{3}{2}}}{\log 3^4}\) = \(\frac{\frac{3}{2} \log 3}{4 \log 3}\) = \(\frac{\frac{3}{2}}{4}\) = \(\frac{3}{8}\)

2s\(^2\) - 3st - 2t\(^2\) = 2s\(^2\) - 4st + st - 2t\(^2\) = 2s(s - 2t) + t(s - 2t) = (2s + t)(s - 2t)

x\(^2\) - 2x - 3 = 0 x\(^2\) - 3x + x - 3 = 0 x(x - 3) + 1(x - 3) = 0 (x + 1)(x - 3) = 0 x = (-1, 3)

\(\frac{5}{6r} - \frac{3}{4r}\) = \(\frac{10 - 9}{12r}\) = \(\frac{1}{12r}\)