1pt The atomic mass and abundance of Si-28 is 27.977 amu and 92.2%. The atomic mass and abundance of Si-29 is 28.976 amu and 4.7%. The atomic mass and abundance of Si-30 is 29.974 amu and 3.1%. Which is the average atomic mass of silicon?
O A. 27.98 amu
OB. 28.09 amu
O c. 28.98 amu
OD. 29.97 amu