Answer:
All energy is made by the sun because without the sun there would be no humans to produce other energy
Scientists should control most possible variables in experiments to get the most valid and correct data. If many variables are included in experiments it is more difficult to interpret what is causing a different outcome.
Answer:
Explanation:
Nitrogen gas in nitrogen cylinder is in gaseous form only . So when gas is released , pressure decreases because moles of gas in the cylinder decreases .
Propane gas in cylinder is in liquified form . The gas is partially in gaseous and liquid form . So when gas is released outside , pressure decreases inside but due to low pressure , some liquid form is converted into gaseous form which restores the pressure of gas inside cylinder . Hence , the pressure of gas remains unchanged inside cylinder.