Mars appears red due to the presence of iron oxide (rust) on its surface, which reflects sunlight in a reddish hue. This gives it the nickname “Red Planet.”
What is the chemical symbol for gold?
A G
B Au
C Ag
D Go
The symbol “Au” comes from the Latin word Aurum, meaning “shining dawn.” Gold is a precious metal known for its luster and malleability.
Which gas is most abundant in Earth’s atmosphere?
A Oxygen
B Carbon dioxide
C Nitrogen
D Hydrogen
Nitrogen makes up about 78% of Earth’s atmosphere, followed by oxygen (around 21%). The remaining 1% includes gases like argon and carbon dioxide.
What is the main function of white blood cells in the human body?
A Carry oxygen
B Help in blood clotting
C Fight infections
D Transport nutrients
White blood cells (leukocytes) are a vital part of the immune system. They help protect the body against bacteria, viruses, and other pathogens.
What is the speed of light in a vacuum?
A 3,000 km/s
B 30,000 km/s
C 300,000 km/s
D 3,000,000 km/s
The speed of light in a vacuum is approximately 299,792 kilometers per second (commonly rounded to 300,000 km/s). It’s the fastest speed at which energy and information can travel.