how to prepare approximately 100 ml of a .12M copper (II) chloride solution using a 50.5% by mass copper (II) chloride that has a density of 1.05 g/ml

Answer 1

50.5% by mass means 50.5 g CuCl2/100 g soln.
Convert that to molarity, then use the dilution formula of
mL x M = mL x M.