50 points: can someone me with this question : a classroom is 5.345m long, 4.128m wide, and 3.859m high. what is the mass of air it contains?

Asimply means that over time there was some sort of change.

What is a neurotransmitter involved in mood reward, addiction, and motor behaviors?

Water is siphoned from a large tank and discharges into the atmosphere through a 50-mm diameter tube. the end of the tube is b = 2.6 m below the tank bottom which is a = 6.7 m deep, and viscous effects are negligible. determine the maximum height h over which the water can be siphoned without cavitation occurring. atmospheric pressure is 101.4 kpa, and the water vapor pressure is 1.79 kpa (absolute). report your answer in meters to two decimal places.