The atmosphere's layers

1. the lowest stratum of the atmosphere
stratosphere
troposphere
mesosphere

2. most of the earth's ozone is located in the
stratosphere
troposphere
mesosphere

3. earth coldest temperature occur in the
stratosphere
mesosphere
troposphere

Air is contained in a variable-load piston-cylinder device equipped with a paddle wheel. initially, air is at 400 kpa and 17°c. the paddle wheel is now turned by an external electric motor until 75 kj/kg of work has been transferred to air. during this process, heat is transferred to maintain a constant air temperature while allowing the gas volume to triple. calculate the required amount of heat transfer in kj/kg.