Explanation

Supplementary angles add up to 180°, so set up an equation:

(3x + 5) + (9x - 5) = 180°

Combine like terms:

12x = 180°

Divide both sides by 12:

x = 15°

Explanation

Explanation

The sentence is a question, so it ends with a question mark (?).

"Shandor" is a proper noun, so it must start with a capital letter.

Explanation

Given:

Breadth = 1/5 × Length

Perimeter = 24m

Let length = L

Breadth = L/5

Perimeter formula: P = 2(L + B)

24 = 2(L + L/5)

24 = 2(6L/5)

24 = 12L/5

24 × 5 = 12L

120 = 12L

L = 10m

Explanation

Blue green algae (also called cyanobacteria) are prokaryotes, meaning they lack a true nucleus and membrane-bound organelles.

Unlike animals and plants (which are eukaryotes), their DNA floats freely in the cytoplasm.

Explanation

• Phenolphthalein is a pH indicator that changes color in response to changes in acidity or basicity.
• In an acidic medium, it is colorless, and in a basic medium, it turns pink.

Explanation

The prefix “pre-” means “before”, as seen in words like preview (before viewing) or predict (say before it happens).

It indicates something happening earlier in time or order.

Explanation

Psychology is the scientific study of behavior and mental processes (thoughts, emotions, etc.).

It explores how people think, feel, and act in different situations.

Explanation

"But" is used to show a contrast between two ideas — here, talent vs. lack of confidence.

It correctly connects the opposing thoughts in the sentence.

Explanation

Alliteration is the repetition of the same starting consonant sound in closely connected words.

In this phrase, the "s" sound repeats in "Silly," "snakes," "slither," and "slowly."