A biochemist carefully measures the molarity of salt in 27. mL of photobacterium cell growth medium to be 12. mM. Unfortunately, a careless graduate student forgets to cover the container of growth medium and a substantial amount of the solvent evaporates. The volume of the cell growth medium falls to 3.9 mL. Calculate the new molarity of salt in the photobacterium cell growth medium. Be sure your answer has the correct number of significant digits.