How do I calculate the concentration of a solution, using 100 μg of Raffinose powder dissolved into 10ml of PBS. I had 3 concentrations used in total; the high dose containing 5400 μl of stock solution (SS) mixed with 600 μl of growth medium (GM), medium dose containing 3000 μl of both SS and GM and the low dose containing 600 μl of SS and 5400 μl of GM.