Why is skin
and stiffener method used​

Stiffeners are employed to resist lateral loading of the plate and are usually made from the rolled shapes integrally welded to the plate. Such stiffeners are distinct from the other stiffeners used to prevent plate buckling. Typically, stiffeners run continuously through the supporting frames. Otherwise they are referred to as “intercostal” and require special connections at each end at each frame.

answer: my answer would be a) scheduling workouts with your friend for consistent days and time

explanation: for me personally i would be much more likely to go to the gym with a friend because i wouldn't want to cancel on them or stand them up.

answer(d) call 911;