In Nepal.
Mountains and hillsand cliffs
There are no exact amount if mountains on Earth. Some are even forming now, so you wouldn't now how much mountains there are on Earth.
=mountains are made from the earth in the ocean=
Upwarped mountains
Earth's mountains form and erode from erupting and by shifting plates.
How much of the earth's surface do mountains cover? it is 99% of the earth
Where can find mountains in the world
The Earth has more valleys than mountains. Valleys are low-lying areas often formed by erosion, while mountains are elevated landforms. Overall, valleys cover a larger surface area on Earth compared to mountains.
You question is meaningless. Earth has mountains as a result of continental drift/plate tectonics, there is no benefit or deficit - mountains just are.
becauuse of the gravity of the earth
Gravity on the moon is one sixth of gravity on the earth, so mountains on the moon can be much taller. Mountains on earth are eroded by wind and water, but on the moon mountains are not eroded.