Explanation

Prime Minister Imran Khan laid the foundation stone of the Kartarpur Corridor on 28 November 2018 near Narowal, Pakistan.

The corridor was established to allow Indian Sikh pilgrims visa-free access to Gurdwara Darbar Sahib Kartarpur.

The corridor was officially inaugurated on 9 November 2019.

Explanation

The Paschen series involves electron transitions ending at the third energy level (n=3) in a hydrogen atom.

These transitions emit photons in the infrared region of the electromagnetic spectrum.

Explanation

"If you lose your passport, you will be in great trouble."

In a first conditional sentence, we use the present simple tense in the if clause and the future simple (will + verb) in the main clause.

Here, "lose" (present simple) is correct because it is used in the if clause to indicate a possible future event.

Explanation

When using future perfect tense ("will have passed"), the clause with "when" takes present simple tense — not future.

So, the correct sentence is: "Three hours will have passed when the bell rings."

Explanation

We are told:

• Circumference of a circle = a

• Area of the circle = b

• And a = b

We know the formulas:

• Circumference:

  $$a = 2pi r$$
  

• Area:

  $$b=\pi r^2$$r=0orr=

Since $a = b$, set the formulas equal:

$$2pi r = pi r^2$$

Divide both sides by $pi$:

$$2r = r^2$$

Rearrange:

$$r^2 - 2r = 0 Rightarrow r(r - 2) = 0$$

So the solutions are:

r=0 or r=2

Explanation

"All will go to Karachi in April."

• "To" is used for direction or destination → go to Karachi.

• "In" is used for months, years, and longer periods → in April.

 So, the correct and natural usage is: to Karachi, in April.

Explanation

Institutions refer to long-standing practices or structures—leadership fits this description.

Passion for knowledge implies a strong desire to understand, making the phrase contextually accurate.

Institutions means ادارے

Passion means جذبہ

Explanation

The eye lens focuses light to form a real and inverted image on the retina.

The brain then processes this image and interprets it as upright.

Explanation

 The correct structure is “so + adjective + that” to show cause and effect.

"The question paper was so complicated that it was completely incomprehensible."

Explanation

 We are given:

• Red balls = 8

• Blue balls = 7

• Green balls = 6

Total balls = 8 + 7 + 6 = 21

We are asked to find the probability that the ball is neither red nor green.

That means we want the probability that the ball is blue.

Number of favorable outcomes = Number of blue balls = 7

Probability = (Favorable outcomes) / (Total outcomes)

= 7/31

=1/3
$$721=13frac{7}{21} = frac{1}{3}