Coal is a fossil fuel and non-renewable energy source. Solar, wind, and hydroelectric are all renewable sources.

Ampere (A) is the SI unit of electric current. Volt is for potential difference, Ohm for resistance, and Watt for power.

Oxygen has atomic number 8. It is essential for respiration in living organisms.

The speed of light in vacuum is approximately 3 × 10^8 m/s or 299,792,458 m/s.

Rusting of iron is a chemical change as a new substance (iron oxide) is formed. Others are physical changes.

Pure water is neutral with a pH value of 7 at 25°C. Values below 7 are acidic and above 7 are basic.

Mars is called the Red Planet due to the presence of iron oxide (rust) on its surface.

Photosynthesis is the process where plants convert sunlight, water, and CO2 into glucose and oxygen.

An adult human body has 206 bones. Infants are born with approximately 270 bones, many of which are cartilage.

Carbon dioxide (CO2) is the primary greenhouse gas responsible for global warming, released mainly through fossil fuel combustion.