At high altitudes, pilots and mountain climbers must breathe an enriched mixture containing more oxygen than the standard 21.0% found in ordinary air at sea level. at an altitude of 10500 m, atmospheric pressure is 0.237 atm. what oxygen concentration is required at this altitude if, with each breath, the same number of oxygen molecules is to enter the lungs as for ordinary air at sea level?

the arctic is a region of the planet, north of the arctic circle, and includes the arctic ocean, greenland, baffin island, other smaller northern islands, and the far northern parts of europe, russia (siberia), alaska and canada.

iron would move it is magnetic there is a mag field around the current in the wire

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.