= The population size of a culture of bacteria triples every hour such that its size is modeled by the sequence an - 150(3)", where n is the number of the hour just beginning. Find the size of the culture at the beginning of the fourth hour and the size of the culture at the beginning of the first hour. At the begining of the fourth hour, the size of the colony is bacteria. At the begining of the first hour, the size of the colony is bacteria.