A \( 1 mL \) sample of a bacterial culture at \( 37^{\circ} C \) is taken, and diluted to \( 10 L \). A \( 1 mL \) sample of the diluted culture is spread on a culture plate. Ten minutes later, another \( 1 mL \) sample taken from the original culture diluted and spread in the same way. The two plates are incubated for 24 hours. The first sample exhibits 48 colonies of bacteria, the second 72 colonies. If we assume that each colon originates with a single bacterium, what is the generation time (time required for doubling th population). (Assume it to be a first order kinetics).
