Explain why the pressure exerted by a gas does not depend on the type of the gas.

Since no matter what type of gas there is there is still a pressure exerted by it. Since the Kinetic theory of gases says " the pressure is proportional to the number of particles in the gas".
Basically pressure exerted by the gas depends rather on the temperature. the temperature increases, and the volume still says the same though. 

70000 cm in 7km

Explanation:

There are 1000 m and 100 cm in 1 m in 1 km, so to find how many cm are in 7 km you need to do 10000 x 7.  You get 70000

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