Explanation

Vexing means پریشان کرنے والا

Annoying means غصہ دلانے والا

Disturbing means پریشان کن

Explanation

Cellular respiration breaks down glucose to produce ATP, the energy currency of the cell.

This energy powers various cellular activities essential for life.

Explanation

Explanation

Since fluorine is more electronegative, its oxidation state is -1.

The molecule OF2 has zero overall charge:

O + 2F = 0

x + 2(-1) = 0

x - 2 = 0

x = +2

Explanation

Engrossed means مشغول

Absorbed means جذب

Explanation

If he works hard, he will pass the examination

This is a first conditional sentence

"If + present simple, will + base form of the verb". 

Explanation

Bragged means شیخی مار

Boasted means گھمنڈ

Explanation

He goes to college daily in time.

The subject "He" is third person singular, so in the present simple tense, we add -s to the verb. 

The sentence describes a habitual action, so the present simple tense is appropriate.

Explanation

The phenomenon where a chemical element exists in multiple crystalline forms is called allotropy

Allotropy refers to the ability of an element to exist in two or more different forms in the same physical state.

This is different from polymorphism, which is a broader term referring to any substance (not just elements) that can exist in multiple crystalline forms. 

Explanation

The weight of a man in an elevator descending with an acceleration of 4.9 m/s² will become:

Let:

• Actual weight $W=mg$

• Acceleration due to gravity g=9.8m/s^2

• Acceleration of the elevator a=4.9m/s^2

When an elevator descends with acceleration $a$, the apparent weight becomes:

W′=m(g−a)

Substitute values:

W′=m(9.8−4.9)=m(4.9)
W′=1​/2×mg

So, the apparent weight becomes half of the actual weight.