A generic element, M, has two isotopes, 11M and 13M, and an average atomic mass of 11.66 amu. The natural abundances of the two isotopes are 65% 11M and 35% 13M. The isotopic mass of 11M is 11.01 amu. What is the isotopic mass of 13M? a) 12,01 amu b) 12.87 amu c) 11.24 amu d) 11.43 amu