Explanation

The primary chemical composition of marble is Calcite. 

Marble is primarily composed of calcium carbonate (CaCO3), which is the mineral calcite. 

Explanation

The sentence expresses regret about the past, so past perfect tense is used.

"I wish I had worked harder" is the correct form to show a past unreal situation.

Explanation

The correct phrase is "worthy of praise", which is standard English usage.

"Of" appropriately links "worthy" with the noun "praise."

Explanation

 The countries with the highest prevalence of modern slavery in Africa are Eritrea, Mauritania, and South Sudan.

Explanation

Wasq is an old Arabic unit of measurement often used for large quantities.

It traditionally associated with a camel's carrying capacity.

It was historically used to measure agricultural produce like dates and grains.

Explanation

 The verse "And hold firmly to the rope of Allah all together and do not become divided"

It is found in Surah Al-Imran (Family of Imran), verse 103.

Explanation

 The verse, "We have created you from male and female and made you peoples and tribes that you may know one another,"

It is found in Surah Al-Hujurat, verse 13. 

Explanation

 The verse "Let there be no compulsion in religion" is found in Surah Al-Baqarah, verse 256.

This verse is a central tenet in Islam, emphasizing religious freedom and individual choice. 

Explanation

The average of the first n natural numbers is given by (n + 1) / 2.

For n = 97:

Average = (97 + 1) / 2

= 98 / 2

= 49

Explanation

Angel Rizwan is appointed as the gatekeeper of Heaven (Jannah).

He welcomes the righteous believers into Paradise.

Angel Malik is the chief gatekeeper of Hell (Jahannam).

He oversees the punishments of the inhabitants of Hell.