Answer:
At the interior side.
Step-by-step explanation:
Nonpolar amino acids of a protein more likely to be found at the interior side of the soluble proteins where they are far from the water because water is a polar molecule and only polar amino acids of protein can interact with the water so that's why the polar amino acids are present on the surface of soluble proteins and the nonpolar amino acids of a protein are present at the interior side of the soluble proteins due to its nonpolar nature.