Can someone plz help me I don’t understand how to do this and I am really struggling with the online stuff

Answer:
A
Step-by-step explanation:
x=6.28111...
100 x=628.111...
1000x=6281.111...
subtract
900x=5653
x=5653/900
density of iodine=785×5653/900≈4930.672222...
Here 2 is repeating .