Everyday Science

In 2016, estimates suggested that the kangaroo population in Australia was about 44 million, which is roughly double the human population of 24 million at that time. This makes option C the correct answer.

AIDS (caused by HIV) is transmitted through specific body fluids such as blood, semen, vaginal fluids, rectal fluids, and breast milk. It spreads primarily through unprotected sexual contact, sharing needles, and from mother to child during pregnancy, childbirth, or breastfeeding. It is not spread through air, water, or casual touch such as hugging or shaking hands. Therefore, none of the options A (Air), B (Water), or C (Touch) are correct modes of transmission. The correct answer is D (None of these).

Salt is commonly mixed with ice on roads in cold countries because it lowers the freezing point of water, causing ice to melt and preventing slipping. Sugar and nitrogen do not have this effect, and "None of these" is incorrect.

A pyrometer is an instrument used to measure very high temperatures, typically in industrial settings, where conventional thermometers cannot be used. Hygrometers measure humidity, altimeters measure altitude, and 'None of these' is incorrect.

Hydrogen is the most abundant element in the universe, making up about 75% of its elemental mass. It is the primary building block of stars and galaxies, far more abundant than nitrogen or oxygen.

The average adult human body contains approximately 5 liters of blood, which supports circulation and oxygen transport throughout the body.

There are two main models for primary colors: the traditional pigment model (RYB) and the RGB model used for light. The traditional primary colors in art and pigment mixing are red, yellow, and blue (RYB). However, in the RGB color model used for digital screens and light, the primary colors are red, green, and blue. Since the question does not specify the model, option A (red, blue, green) correctly identifies the primary colors in the RGB model, which is commonly taught in science and digital contexts. The other options list incorrect combinations or colors not considered primary in either model.

Elements in the periodic table are arranged based on their atomic number, which is the number of protons in the nucleus of an atom. This arrangement reflects the periodicity of element properties.

Nitrogen is the principal element of the Earth's atmosphere, making up about 78% of it by volume, which is why option B is correct. Oxygen is the second most abundant, but not the principal element.

Dry ice is the solid form of carbon dioxide (CO2). It sublimates directly from solid to gas at atmospheric pressure without becoming liquid.

On average, a human breathes about 11,000 liters of air per day, considering normal respiratory rates and tidal volumes. This makes option A the correct choice.

Long-sightedness (hypermetropia) is corrected using convex lenses because they converge light rays before they enter the eye, helping focus images correctly on the retina.

Physiology is the branch of biology that studies the normal functions and processes of living organisms and their parts. Therefore, option B correctly describes physiology as the study of normal functions in living creatures.

The unit of electric current is the Ampere, which measures the flow of electric charge per second. Joule is a unit of energy, and Watt is a unit of power, so they are incorrect in this context.

Vitamin A deficiency primarily causes night blindness because it impairs the retina's ability to function in low light conditions. This is a well-established fact in nutrition and health science.

Vitamin D deficiency leads to rickets, a condition characterized by soft and weak bones in children due to impaired calcium absorption. Smallpox and measles are viral infections unrelated to vitamin D levels.

Oxygen is the most abundant element in the Earth's crust, making up about 46% by weight. Nitrogen and hydrogen are not major components of the crust, so option C is correct.

Alexander Graham Bell is credited with inventing the telephone in 1876, making option B the correct answer. Samuel F. B. Morse invented the telegraph, Thomas Savery invented an early steam pump, and 'None of these' is incorrect.

Mount Everest, the world's highest mountain, is located in Nepal. It is part of the Himalayas and is the tallest peak on Earth.

Fossil fuels have been known and used as a source of energy since the mid-17th century, making option A the correct answer. The other options are either incorrect or nonsensical.

Jabir bin Hayyan is widely regarded as the father of chemistry due to his pioneering work in alchemy and chemical processes, which laid the foundation for modern chemistry. The other options are notable Muslim scholars but not specifically credited as the founder of chemistry.

Jabir bin Hayyan is widely regarded as the founder of chemistry due to his pioneering work in alchemy and chemical processes, which laid the foundation for modern chemistry. The other options are notable Muslim scholars but not credited with founding chemistry.

Rearranging the letters in "MANGERY" forms the word "GERMANY," which is the name of a country. Therefore, the correct answer is C (COUNTRY).

By comparing the messages, 'Elendil' appears in the first message meaning 'Explosion' and is also associated with the word 'Explosion' in the third message. Therefore, 'Elendil' means 'Explosion'.

The question asks which letter among the five is least like the others. The options given are letters E, A, C, and B. Among these, 'E' is the least like the others because the other letters (A, B, C) are among the earliest letters in the alphabet and are often grouped together, while 'E' stands apart as a different letter in this set. This type of question tests pattern recognition and categorization skills, where the odd one out is identified based on alphabetical grouping or commonality.