Can u pls help me with this question

In a laboratory, 1.55mg of an organic compound containing carbon, hydrogen, and oxygen is burned for analysis. this combustion resulted in the formation of 1.45mg of carbon dioxide and .89 mg of water. what is the empirical formula for this compound?

To apply in a gold the individual gold atoms are united to each other by means of a metallic bond. how would you use the gold block to determine the atomic radius of a gold atom?

A5.00 g of a in . g of at aa 5.00 g of b in . g of .?at .