Answer:
d) Interaction between Arg and Lys side chains at a pH of 7, assuming standard pKa values for Arg and Lys.
Explanation:
Arginine and Lysine are basic amino acids. They play same role in various membrane proteins. They both have high aqueous values which give rise to high electrostatic interaction. The interaction is mainly in the cations of the side chains. They both are heterologous secreted proteins which plays role of metabolite.
Answer: B. trigonal planar
Explanation:
Valence Shell Electron Pair Repulsion Theory (VSEPR) is a model to predict the geometry of the atoms making up a molecule where atoms are arranged such that the forces of repulsion are minimum.
If a central atom is bound to three electron domains ,the number of electron pairs is 3, that means the hybridization will be 
and the electronic geometry of the molecule will be trigonal planar as the electron pairs will repel each other and attain a position which is most stable.
Example: 
with 3 electron domains has trigonal planar geometry.
Answer:
c
Explanation:
because nothing is changing, so what are you gonna track with the line graph
