The Chemistry of Nicotine

Nicotine, a component of tobacco, is composed of C, H, and N. A 5.250-mg sample of nicotine was combusted producing 14.242 mg of CO2 and 4.083 mg of H2O. What is the empirical formula for nicotine? If the substance has a molar mass of 160 ± 5 g/mol, what is its molecular formula?
Please convert from mg to g.