Question 2 [10 marks total]: You have an unknown peptide that gives an m/z of 920.2Da for a singly charged ion when analyzed by MALDI-MS. You suspect this peptide residue is methylated on two residues of the peptide. You subject the peptide to mass spectrometry fragmentation. Based on the "B" and " Y " ions provided below, propose a sequence (using 1 or 3 letter amino acid code) for the peptide molecule and indicate which two residues contain a methyl group. Note that methylation adds 14Da to the mass of the residue that it modifies. Explain your reasoning and show your work