Ce - 141; 3.2mu * C * i after 130 The half - life for the radioactive decay of is 3.9 Ci after 195 d have elapsed , what was the initial activity in microcuries , of the sample ?

each  column  of the  table  is called a group. elements in a group share similar properties. groups are  read  from  top  to  bottom. metal. metalloid. nonmetal. solid. liquid. gas. fe. hg. o.  2. 3. 4. 5. 6. 7. 8. 9.  2. beryllium. 9.012. 4.  sodium. 22.990.  11. 3.  magnesium. 24.305.  12.  potassium. 39.098.  19. 4.  calcium. 40.078.  20. i guess  i  

fe 55.85 g/mol and h2o 18.02 g/mol.