Naturally occurring cobalt consists of only one isotope, 59Co , whose relative atomic mass is 58.9332. A synthetic radioactive isotope of cobalt, 60Co , relative atomic mass 59.9338, is used in radiation therapy for cancer. A 1.7320 g sample of cobalt has an apparent "atomic mass" of 58.9901. Find the mass of 60Co in this sample. Express your answer with the appropriate units.

Express no of atoms using four significant figures

21.899 g Cr

46.347 gS

12.360 g Pt

96.471 g Sn