4. To determine the frequency of ala mutants a fluctuation test was done using 30 tubes with a final concentration of 108 bacteria each. From
each tube 0.1 ml of culture was plated on medium that selects for ala
mutants. 27 of the tubes yielded ala mutants but 3 of the tubes yielded
no mutants. Based upon these results, use the Luria-Delbruck
calculation to determine the mutation rate to ala.