Explanation

Now Maryam was shifted to 4 places to the right.

This implies her place is x+4 from left now, but it is given that her new place is 12th from left.

Now, in a row of 21 girls, her place is 8,

which is 14th place from right.

Explanation

The logic followed here is:

Saqib ranks seventh from the top and twenty-eight from the bottom in the class

Number of students in the class= 7 + 28 -1 

                                                        =  34

Explanation

Total no. of students = Top position + Bottom position - 1

Total no. of  students =16+49−1

                                      = 64

****

Number of students in the class $=(15+1+48)=64$

Explanation

50 - ( 10 + 25 ) = 15 

Khadija is middle of  15

= 8 + 10 

= 18th

Explanation

He was unfit for the job

وہ اس کام کے لیے نااہل تھا۔

unfit for use means: not suitable or good enough for a particular purpose or activity

Explanation

All matter consists of atoms,

which, in turn, consist of protons, neutrons and electrons.

Explanation

"He wrote a letter yesterday" is the simple past tense expressing the completion of the action of writing in the past. 

Since 'yesterday' is mentioned, we can understand that the letter had been written in the past.

Therefore, we take the simple past form of 'write.'

Explanation

The cat is UNDER the table

In this sentence, the word "under" showcases the location of the cat (subject) with regard to the table (object),

hence under is a preposition.

The words "cat" and "table" are nouns and "under" is used after the subject noun

Explanation

Carbon-12 (12C) is the most abundant of the two stable isotopes of carbon (carbon-13 being the other), amounting to 98.93% of element carbon on Earth;

its abundance is due to the triple-alpha process by which it is created in stars.

Explanation

The speed of sound is the distance travelled per unit time by a sound wave as it propagates through an elastic medium.

The speed of sound is 343.2 metres per second.