Shell structure
it is a frame sturctures
a teepee is a frame structre
its a frame
its "MIXED" : shell,frame, mas. BUT u can say its shell if u didnt learn the word mixed.
mass
sheel
mass
eiffel tower is a frame structure.
shell because it is hollow and therefore represents the form of a shell which is also recognized as a shell structure
frame structure
the Eiffel tower is a definite frame. if the tower had something over the frame it would be a mass so the Eiffel tower would never be a shell if it had the framing still inside of it.