Would any of our members know anything about strength and materials? Here is the senerio, bridging a 4 ft. span, which would hold more weight when placed directly in the middle (centered 2ft. from each end)?
material would be mild steel (same in all cases) 1/8 inch thick wall except #4, 1/4 thick
for simplicity only one piece with no bracing or any other type of support
1. 2" round tubing
2. 2" square tubing
a. w/flat top & bottom level w/floor
b. w/flats at 45degrees to floor
3. 2" angle iron boxed with like material to form a triangle
a. w/boxed side level w/floor top
b. w/boxed side level w/floor bottom
4. 2" angle iron w/sides twice the thickness of 1,2,&3 in any clocking

thanks Denny

Is this your homework??

I have a book on this stuff and bunch of homework.
If this is from from a college book, give me the name and edition and I might have some homework on this I could email you.

Find the moment of inertia for each of the scenarios and that will be the one that will hold the largest load.

clarify, largest moment = largest load (hint: generally, not always, the shape with the most material farthest away from the neutral line will also have the highest moment)