Explanation

Insulin is the hormone secreted by the pancreas, which plays a crucial role in regulating blood sugar levels.

It helps in the metabolism of proteins, starches, and fats by facilitating the absorption of glucose into cells.

Explanation

A White Dwarf is the remnant of a low or medium-mass star (like our Sun) after it has exhausted its nuclear fuel (hydrogen and helium).

It no longer undergoes fusion and slowly cools over billions of years.

Explanation

Mercury remains liquid at a wide range of temperatures, has uniform expansion.

It is easily visible due to its opacity.

It does not stick to glass, allowing accurate and consistent readings in thermometers.

Explanation

Bacteria are single-celled microorganisms that can exist in various environments, including the human body.

They can be both beneficial (like in digestion) or harmful (causing infections).

Explanation

Given:

40% of employees didn't go to the meeting, and this equals 28 employees:

40% of x = 28

(40/100)x = 28

0.4x = 28

x = 28 / 0.4

x = 70

Explanation

James Harrison, an Australian inventor, is credited with creating the first practical refrigeration system in 1856.

His work laid the foundation for modern refrigeration technology, which was crucial for preserving food and other goods.

Explanation

First, convert both to the same unit (grams):

3.5 kg = 3500 grams

280 grams (already in grams)

Ratio = 3500 : 280

Simplifying the ratio:

3500 / 280 = 12.5

280 / 280 = 1

12.5 : 1 = 25 : 2 (after multiplying both parts by 2)

Explanation

The Black Hole of Calcutta incident happened in 1756 when British prisoners were allegedly confined in a small room by the troops of Nawab Siraj-ud-Daula.

This event was one of the factors that led to the Battle of Plassey in 1757, where Siraj-ud-Daula was defeated by the British.

Explanation

The mistress enquired of Fanny if she had mailed the two letters she gave her the day before.

The reporting verb "enquired" changes the direct speech into indirect speech.

The past tense verb "gave" and the time word "yesterday" correctly change to "the day before" in indirect speech.

Explanation

In space, beyond Earth's atmosphere, the sky actually looks black because there is no air to scatter sunlight.

The blue color we see from Earth is due to Rayleigh scattering in the atmosphere, not the actual color of the sky.