Explanation

• Karl Landsteiner discovered the ABO Blood Group System in 1900.
• He was an Austrian scientist and physician.
• His discovery made safe blood transfusions possible.
• He received the Nobel Prize in Physiology or Medicine in 1930 for his work.

Last verified on 01-07-2026

Explanation

• Chile saltpeter is the common name for sodium nitrate (NaNO₃).
• It is found naturally in Chile and Peru.
• It is used in fertilizers and explosives.

Last verified on 18-06-2026

Explanation

• Ascorbic Acid is commonly known as Vitamin C.
• It is essential for growth, repair, and maintenance of body tissues.
• Prevents scurvy, a disease caused by Vitamin C deficiency.

Additional information:

Sources of Vitamin C (5):

1. Orange
2. Lemon
3. Guava
4. Strawberry
5. Bell pepper

Functions:

• Antioxidant
• Collagen synthesis
• Strengthens immunity

Last verified on 19-01-2026

Explanation

• Conceited means مغرور
• Bossy means دبنگ اور حد سے زیادہ اعتماد
• Impudent means غیر منقولہ

Explanation

Indolent means کام چور یا سست

Lazy means کام سے جی چرانے والا

Explanation

I have never known him for a long time.

میں اسے ایک عرصے سے کبھی نہیں جانتا تھا۔

"Have never known" is the correct present perfect tense.

It indicating that up until now, the speaker has never known the person.

Explanation

The study of viruses is called virology.

Virology encompasses the study of viruses, their structure, classification, evolution, and how they interact with living organisms.

Explanation

The SI unit of impedance is the ohm (Ω).

Impedance, like resistance, is measured in ohms.

It can be represented as a complex number.

Explanation

Felicity means خوشی یا راحت

Happiness means خوشی

Explanation

The pair of physical quantities with the same dimensions is Work and Energy.           

Both work and energy have the same dimensional formula: ML²T⁻²