Imagine that you and roommate/friend/sibling/parent are having a heated discussion about how to build a safe walking path that you can both use (at the same time) to cross the 8 ft diameter hole outside of the door to your house (note: the discussion is NOT about why there is an 8 ft diameter hole outside of the door to your house). You want to use 2x4(s) to span the hole as a temporary bridge, your roommate/friend/sibling/parent wants to use a rope swing. Do the engineering analysis to convince yourself of the 2x4 option. Provide a few free body diagrams of different configurations of point loads crossing the hole over the 2x4 bridge and draw the corresponding shear and bending moment diagrams for each case to determine the maximum moment you expect to encounter. Assume an allowable normal stress and with your maximum moment (from the bending moment diagram) determine the minimum Section Modulus. How many 2x4s and in what configuration (lying flat or standing upright) will work? Next, go and actually talk to your roommate/friend/sibling/parent and convince them of your design. Provide a write-up of both: your engineering analysis; and a summary of how the discussion went.