How much of the earth’s atmosphere is made up of nitrogen and oxygen?

How much of the earth’s atmosphere is made up of nitrogen and oxygen?

It is primarily composed of nitrogen (78%) and oxygen (21%) with only small concentrations of other trace gases. Nearly all atmospheric water vapor or moisture is found in the troposphere, so it is the layer where most of Earth’s weather takes place.

What was the first metal used by man?

Over 4,000 years ago, when it was discovered that minerals could be melted, curiosity led man to combine melted metals (alloys). By accident they made bronze by adding tin to copper (the Bronze Age). Another combination of zinc and copper made brass.

What was Harry Truman’s middle name?

He didn’t have one. The S in Harry S. Truman did not stand for anything.

Who led the first expedition around the world?

Ferdinand Magellan (1480-1521) was a Portuguese explorer who led the first expedition that sailed around the Earth (1519-1522).

Do salmon die after they spawn?

The salmon run is the time when salmon, which have migrated from the ocean, swim to the upper reaches of rivers where they spawn on gravel beds. After spawning, all Pacific salmon and most Atlantic salmon die, and the salmon life cycle starts over again.

How much does the temperature change with altitude?

Although the actual atmospheric lapse rate varies, under normal atmospheric conditions the average atmospheric lapse rate results in a temperature decrease of 6.4C°/km (3.5F°/1,000 ft) of altitude above ground level. The measurable lapse rate is affected by the moisture content of the air (humidity).

What color is between red and blue?

In between these colours may be seen secondary colours that are, perceptually, each a mixture of two of the primaries. Thus, you will see yellow between red and green, and cyan blue between green and blue-violet. The third secondary colour of light is magenta.

Who was the god of love?

Eros (/ˈɪərɒs/ or US /ˈɛrɒs/; Greek: Ἔρως, “Desire”), in Greek mythology, was the Greek god of love. His Roman counterpart was Cupid (“desire”). Some myths make him a primordial god, while in other myths, he is the son of Aphrodite.