Answer:
21 minutes or 0.35 hours
Explanation:
The formula for exponential population growth is
where
initial population of E.coli i.e 100
k is the rate of population growth i.e 2 as the population doubles
t is the time period i.e 20 minutes
Substituting the given values in above equation, we get -
Generation time
minutes
or 0.35 hours