The number N of bacteria in a culture is given by the model
N = 220ekt,
where t is the time (in hours), with t = 0 corresponding to the time when N = 220. When t = 10, there are 310 bacteria. How long does it take the bacteria population to double in size? To triple in size? (Round your value of k to five decimal places. Round your final answers to two decimal places.)
double ___ hr
triple ___ hr
