Apolypeptide in its native conformation has weak interactions between its r groups. however, when that same polypeptide is denatured, these r groups similarly interact with water. why, then, is the native structure more stable than the denatured one

A protein is more stable in its native form, because apart of weak interactions between R groups, it also presents other stronger interactions, as those including covalent bonds  

Explanation:

For example, covalent bonds between sulfur atoms when disulfide bridges are built.  These links are very difficult to break and maintains the protein shape.  Disulfide bonds are a few but they use to incide in the structure of native proteins

practical process described pest part of scientific investigation.

because practical knowledge is powerful then therotical knowledge.

the positions which points up in upward carbon and down in downward carbon are axial

and vice versa holds true for equatorial positions

so the correct answer with labelled diagram will be