Jake stole a suspension of Bacillus anthracis with a known concentration of 7 x 107 spores/mL. He wants to dilute this cell suspension down to 2 x 103 spores/mL. Calculate his dilution factor. Design and draw a practical dilution scheme which limits the volumes used to greater than or equal to 0.1 mL and less than or equal to 10 mL. (hint: use one-step and serial dilutions together to satisfy the given volume restrictions).