Explanation

HTML provides 6 levels of heading tags: <h1> to <h6>, with <h1> being the largest and most important.

These tags are used to define headings and organize content hierarchically on web pages.

Explanation

Thinking is not a computer operation because computers do not possess consciousness or reasoning like humans.

Computers perform Input, Processing, Storage, and Output, but they follow pre-defined instructions.

Explanation

ROM (Read-Only Memory) is non-volatile.

This meaning it retains data even when the power is turned off.

RAM is volatile.

Explanation

60% of 75 = (60/100) × 75

= 0.6 × 75 = 45

Explanation

x + 3y = 53

4x - 2y = 2

x = 8

y = 15

Explanation

Web 2.0 emphasizes human collaboration, user-generated content, and social interaction through platforms like social media, blogs, and wikis.

It focuses on a more dynamic and interactive web experience compared to the earlier, static Web 1.0.

Explanation

Professional Development refers to a teacher’s efforts to improve and manage their teaching skills, knowledge, and practices.

It includes ongoing learning, training, and reflection to stay effective and current in the profession.

Explanation

In the number 6,985,621, the digit 2 is in the tens place.

Therefore, its place value is 2 × 10 = 20.

Explanation

Dry ice sublimation is a physical change where solid CO₂ directly turns into gas without changing its chemical composition.

Rusting of iron, burning of wood, and cooking of egg are all chemical changes, where new substances are formed.

Explanation

The main enzyme used to make cheese is rennet (also known as rennin).

Rennet is a milk-clotting enzyme that causes milk to curdle, which is a crucial step in cheese production.