What causes us to perceive objects in three dimensions? a. objects in 3-D appear to have width and height, but no depth

b. light bouncing or reflecting off an object in different ways

c. The curvature of space-time relative to objects solar mass

d. The rate of time dilation as we approach objects

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.