A culture of bacteria triples after 7 hours.

What proportion of the original number of bacteria Q0 will be present after 14 hours?
What proportion of the original number of bacteria Q0 will be present after 28 hours?

you can go through the math Q=Q0*3^(t/7) but you will note that the two times are 2 and 4 tripling periods, so there will be 9 and 81 times as many bacteria