Explanation

Paleontology is the branch of science concerned with the study of fossils and the history of life on Earth

Fossils are the remains of plants, animals, fungi, bacteria, and single-celled living things

that have been replaced by rock material or impressions of organisms preserved in rock.

y.

Explanation

Sulfur and nitrogen compounds in the atmosphere can combine with water and oxygen to form sulfuric acid and nitric acid, leading to acid rain.

Acid rain is a type of precipitation that contains high levels of sulfuric and nitric acid, which can harm the environment, infrastructure, and human health.

Explanation

Air is a homogeneous mixture of the gaseous substances

nitrogen,

oxygen, 

smaller amounts of other substances.

Explanation

Objects that orbit around a planet are called satellites.

These can be natural, like the Moon, or artificial, like communication satellites.

Explanation

Systolic pressure, the top number in a blood pressure reading, represents the pressure in arteries when the heart beats.

A normal value is approximately 120 Torr (mmHg).

Explanation

Bituminous coal also called soft coal is middle-rank coal between sub-bituminous and anthracite.

Explanation

The color of a star is directly related to its temperature.

Hotter stars appear blue or white, while cooler stars appear red.

Explanation

1. Mercury

Swift Planet for Mercury

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2. Venus

Eight planets in the solar system

Explanation

White blood cells (leukocytes) are part of the immune system.

They play a key role in defending the body against infections, diseases, and foreign invaders.

They help maintain overall health.

Explanation

The SI is made up of 7 base units

that define the 22 derived units with special names and symbols, which are illustrated in NIST SP 1247, SI Base Units Relationship Poster.