CBC DEMO

The chemical symbol for water is H2O, which indicates it consists of two hydrogen atoms and one oxygen atom. The other options (H2O2, O2H, H2O3) represent different compounds and are incorrect.

Mars is known as the Red Planet due to its reddish appearance, which is caused by iron oxide (rust) on its surface. This distinguishes it from other planets like Jupiter, Venus, and Saturn.

Plants make their food through photosynthesis, a process that uses sunlight, carbon dioxide, and water to produce glucose and oxygen. This is essential for their growth and energy.

The mitochondria are known as the powerhouse of the cell because they generate ATP, the energy currency of the cell, through cellular respiration. This makes them essential for energy production.

The force that pulls objects toward the Earth is gravity. It is responsible for the ball coming back down after Prisha throws it up, as gravity acts on all objects with mass.

Living beings, including humans, need oxygen to breathe. The plants Aashi and Neha are near likely produce oxygen, which is essential for their comfort while exploring the forest.

The smallest unit of life is the cell. Cells are the basic building blocks of all living organisms, while organs, tissues, and organisms are made up of multiple cells.

The heart is the main organ of the circulatory system, responsible for pumping blood throughout the body. The kidneys, lungs, and liver have different functions and are not the primary organs of this system.

The speed of light in a vacuum is precisely 299,792,458 meters per second, making it the fastest speed in the universe. This value is a fundamental constant in physics.

The basic unit of matter is the atom. Atoms combine to form molecules and compounds, but they are the fundamental building blocks of all matter. Cells are biological units, not basic units of matter.