I'm pretty sure it's 9726 milligrams of iodine. Hope this helps.
The formula Ca(ClO3)2 breaks down to: 1 calcium atom, 2 chlorine atoms, and 6 oxygen atoms. Therefore:
One molecule of calcium chlorate contains 9 atoms [correct]
Calcium chlorate is not an element, nor does the molecule contain only 3 atoms [incorrect]
It does not take 9 different elements - just the three elements we listed [incorrect]
Calcium chloride only contains one Ca group [incorrect]