In our laboratory class we were required to calculate the stock (mM) and final (µM) concentrations for Glycerol. The tutor said my final calculations were incorrect and that I had made an error. He didn't have enough time show me where I went wrong. I have compared my results with another student who was told their calculations were correct. I have expanded my calculations to try and identify the problem but I cannot see where I am going wrong. Is there an error in my calculations?