Explanation

Dot pitch (also known as pixel pitch) is the distance between two same-colored pixels on a screen.

A smaller dot pitch means a sharper and clearer display quality.

Explanation

The headmaster usually handles staffing, controlling, and coordinating within the school.

Recruiting is typically done by higher authorities or education departments, not the headmaster directly.

Explanation

Educational management primarily focuses on people (men) — including teachers, students, and administrators.

It aims to effectively organize, guide, and develop human resources to achieve educational goals.

Explanation

"She's been known to sing beautifully", commented Ali.

Quotation marks are used to enclose the exact words spoken, which are: She's been known to sing beautifully.

The speaker (Ali) comes after the quote, so the quotation marks begin and end around the spoken words.

Explanation

The sentence is in present perfect tense ("have lost"), so the passive form is "have been lost."

Subject "we" changes to "by us" in the passive voice, making the correct form: "Our keys have been lost by us."

Explanation

Hydrolysis of one mole of ATP to ADP and inorganic phosphate releases approximately 7.3 Kcal of energy.

This energy is used to power various biological processes in cells.

Explanation

Alkanes are saturated hydrocarbons containing only single covalent bonds between carbon atoms.

They follow the general formula CnH2n+2.

It include compounds like methane, ethane, and propane.

Explanation

A nucleophile is a chemical species that is attracted to positive charges, especially the nucleus.

It donates a pair of electrons to form a chemical bond, often attacking electrophilic centers.

Explanation

Alkenes are commonly known as Olefins due to their ability to form oily liquids when reacting with chlorine.

They are unsaturated hydrocarbons containing at least one carbon-carbon double bond (C=C).

Explanation

Barium (Z = 56) → Electron configuration:

[Xe]6s²

Barium's electron distribution:

• K = 2
• L = 8
• M = 18
• N = 18 ⬅ Penultimate shell (4th shell / N-shell)
• O = 8 (valence shell)

The penultimate shell (N-shell) holds 18 electrons in Barium.