The total momentum of a remains constant through time, regardless of changes within the system.

open system
closed system
generic system
all of the above
none of the above

the working equation for the angular size is the product of the physical size and 360 degrees divided by the product of two pi and distance from earth. the minimum size would be 0.559 degrees while the maximum size would be 0.49 degrees. 

magnified images possible images can be real = projected onto a screen