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.

Where did the name Manhattan come from?

The name Manhattan derives from the word Manna-hata, as written in the 1609 logbook of Robert Juet, an officer on Henry Hudson’s yacht Halve Maen (Half Moon). A 1610 map depicts the name as Manna-hata, twice, on both the west and east sides of the Mauritius River (later named the Hudson River).

How fast does the tube go?

In central London, trains cannot drive faster than 30-40mph because of the short distances between stations. The Victoria line can reach speeds of up to 50mph because the stations are further apart. The Metropolitan line has the fastest train speeds, sometimes reaching over 60mph.

How many pages can you make out of a tree?

Since trees are different sizes, it would be difficult to say how much paper comes from one tree. According to one paper manufacturer, however, a cord of wood measuring 4 feet by 4 feet by 8 feet—or 128 cubic feet—produces nearly 90,000 sheets of bond-quality paper or 2,700 copies of a 35-page newspaper.

Is gray a color?

Grey or gray (see spelling differences) is an intermediate color between black and white. It is a neutral or achromatic color, meaning literally that it is a color “without color.” It is the color of a cloud-covered sky, of ash and of lead.

Which one of the 7 wonders of the ancient world is still standing?

Of the original Seven Wonders, only one—the Great Pyramid of Giza (also called the Pyramid of Khufu, after the pharaoh who built it), the oldest of the ancient wonders—remains relatively intact. The Colossus of Rhodes, the Lighthouse of Alexandria, the Mausoleum at Halicarnassus, the Temple of Artemis and the Statue of Zeus were all destroyed. The location and ultimate fate of the Hanging Gardens are unknown, and there is speculation that they may not have existed at all.

How fast does the human heart beat per minute?

For adults 18 and older, a normal resting heart rate is between 60 and 100 beats per minute (bpm), depending on the person’s physical condition. For children ages 6 to 15, the normal resting heart rate is between 70 and 100 bpm. Athletes and those in excellent physical condition can have resting heat rate of 40 bpm.

How long does it take for your eyes to adjust to the darkness?

On an average it takes 30 to 45 minutes for your rods to be fully dark adapted to night vision. It also covers things such as Mesopic vision and Scotopic vision, eye health, and how to actually dark adapt. I suggest it as a good read.