Correct Answer: A. amplitude

Correct Answer: B) Bromine water

Explanation

Butene and benzene are two different types of hydrocarbons. Butene is an alkene, which contains a carbon-carbon double bond, while benzene is an aromatic compound with a ring structure and alternating single and double bonds.

Alkenes, like butene, undergo addition reactions due to the presence of the carbon-carbon double bond. One such reaction is with bromine water. When bromine water is added to butene, the orange color of bromine water disappears, and a colorless dibromo compound is formed. This reaction is known as the bromine test and is used to distinguish alkenes from other types of hydrocarbons.

On the other hand, benzene does not react with bromine water under normal conditions because the aromatic ring is more stable and less reactive than a carbon-carbon double bond. Benzene can react with bromine only in the presence of a catalyst, such as FeBr₃, and the reaction is a substitution rather than an addition.

Therefore, butene can be distinguished from benzene by its reaction with bromine water (Option B). The other options, hydrochloric acid (Option A), potassium sulfate (Option C), and sodium hydroxide (Option D), do not react with either butene or benzene in a way that would distinguish them.

Correct Answer: B. any

Explanation

Is there any chalk in the classroom?

Any; used to refer to one or some of a thing or number of things, no matter how much or how many.

Correct Answer: A. similarity

Correct Answer: A. sovereignty

Correct Answer: B. Laide

Correct Answer: D. representative democracy

Correct Answer: A. Alaq

Correct Answer: B. \(\frac{-\sqrt{3}}{2}\)

Explanation

\(\cos (x + y) = \cos x \cos y - \sin x \sin y\)

\(\cos (\frac{\pi}{2} + \frac{\pi}{3}) = \cos \frac{\pi}{2} \cos \frac{\pi}{3} - \sin \frac{\pi}{2} \sin \frac{\pi}{3}\)

= \((0 \times \frac{1}{2}) - (1 \times \frac{\sqrt{3}}{2})\)

= \(0 - \frac{\sqrt{3}}{2} = -\frac{\sqrt{3}}{2}\)

Correct Answer: D. Lagos

Explanation

The World Festival of Black Arts and Culture, also known as FESTAC, was hosted by Nigeria in 1991. The event took place in Lagos, which is Nigeria's most populous city and a major cultural hub.