Explanation

RBCs lack a nucleus to make more room for hemoglobin, which carries oxygen.

This structure helps them efficiently transport oxygen throughout the body.

Explanation

Explanation

Climb means اوپر جانے کے لئے

Fall means نیچے جانے کے لئے

Explanation

Cling means مضبوطی سے تھامے رکھنا یا کسی چیز پر قریب سے رہنا

Attach means مضبوطی سے تھامے رکھنا یا کسی چیز پر قریب سے عمل کرنا

Explanation

A surd is an irrational number or expression containing a square root, cube root, etc., that can't be simplified to a rational number.

Example: √2, ³√5 are surds because they involve radical signs.

Explanation

Curiosity means تجسس

Concern means تشویش

Explanation

Desperately means شدت سے یا مضبوطی سے

Hardly means بمشکل یا بالکل نہیں

Explanation

"During" is used to indicate something happening within a period of time, like "childhood".

So, "died during their childhood" is grammatically correct.

Explanation

Certain means کچھ

Some means کچھ

Explanation

An angle inscribed in a semicircle is always 90° due to the Thales' Theorem.

It is called a right angle because the angle subtended by a diameter is always right.