Explanation

• The mass number (A) is the sum of protons and neutrons present in the nucleus of an atom.
• It is a measure of the total number of nucleons (protons and neutrons) in the nucleus.
• It helps determine the atomic mass and distinguishes isotopes of an element.

Last verified on 19-03-2026

Explanation

• Halazone tablets are used to purify drinking water by killing bacteria and pathogens.
• Commonly used in emergencies, military, or travel situations where safe water is unavailable.
• Halazone tablets can purify 1 liter of water in about 5–10 minutes.

Last verified on 19-03-2026

Explanation

• About 97.5% of the water on Earth is saltwater, found in oceans, seas, and salt lakes.
• The remaining 2.5% is freshwater, found in rivers, lakes, wetlands, and underground aquifers.

Last verified on 19-03-2026

Explanation

• Cat and Dog is/are a secondary consumer.
• Because they eats primary consumers (herbivores).
• Like mice, birds, and rabbits.

Last verified on 19-03-2026

Explanation

• Stomata are tiny pores on the surface of leaves that allow gas exchange (CO₂ in, O₂ out).
• They play a key role in photosynthesis and transpiration.
• Number per leaf: Thousands, varies by plant

Last verified on 19-03-2026

Explanation

• The olfactory bulb is a structure in the brain responsible for processing smells detected by the nose.
• It receives signals from olfactory receptor neurons and sends them to other brain regions for interpretation.
• Location: underside of the frontal lobe of the brain

Last verified on 19-03-2026

Explanation

• The ear canal (external auditory canal) transmits sound waves from the outer ear to the eardrum in the middle ear.
• It acts as a conduit, amplifying sound slightly and protecting the inner structures.
• Ear Canal length: ~2.5 cm in adults

Last verified on 19-03-2026

Explanation

• The iris is the colored part of the eye (blue, brown, green, etc.).
• It controls the size of the pupil, regulating how much light enters the eye.

Additional information:

• Pupil – black opening for light
• Cornea – transparent front layer
• Lens – focuses light
• Retina – receives image

Last verified on 19-03-2026

Explanation

Sum of 5 numbers = 5 × 13 = 65

Sum of 4 numbers = 4 × 10 = 40

Fifth number = 65 - 40

= 25

Last verified on 19-03-2026

Explanation

Let youngest child's age = x

Other ages = x+5, x+10

Sum of ages = x + (x+5) + (x+10) = 36

3x + 15 = 36

3x = 21

x = 7

Last verified on 19-03-2026