Explanation

A school can be described as:

1. A social laboratory for children – It serves as a space where children experiment with social interactions, learn cooperation, and develop interpersonal skills.
2. A model social centre – It represents a microcosm of society, teaching norms, values, and civic responsibilities.
3. Responsible for awakening the sense of collective life – It fosters teamwork, community spirit, and an understanding of shared responsibilities.

Thus, a school encompasses all these roles in shaping individuals for societal participation.

Explanation

Administrative decision-making is generally based on logic, analysis, and facts, making it rational.

It aims to choose the most effective solution after evaluating all possible options.

Explanation

The judge ordered the witness to tell the truth.

The verb "said" is replaced with "ordered" because it's a command.

The structure "to tell" is used in the indirect speech, and the tense remains the same.

Explanation

Gastric juice is composed of approximately 90% water, which helps dissolve food and enzymes.

The remaining 10% includes hydrochloric acid, enzymes like pepsin, and mucus.

Explanation

Marijuana is derived from the dried parts (flowers, stems, seeds, leaves) of Cannabis sativa.

It contains psychoactive compounds like THC.

Explanation

Potassium (K) regulates stomatal opening/closing by controlling guard cell turgidity, reducing water loss (transpiration).

It maintains osmotic balance.

Explanation

Environmental psychology studies the interaction between humans and their surroundings, including natural and built environments.

It focuses on how environments influence behavior, well-being, and cognition.

Explanation

A probe is a short, single-stranded DNA or RNA sequence that binds to a complementary gene of interest.

It is used to screen genomic libraries for specific genes.

Explanation

Lithotripsy is a non-invasive method that uses shock waves to break medium-sized kidney stones.

The stone fragments then pass out naturally through urine.

Explanation

Bayer's test (using dilute potassium permanganate) detects the presence of C=C double bonds in alkenes.

A positive test results in decolorization of the purple KMnO₄ solution.