A bacterium divides every 35 minutes. If a culture containing 105 cells/mL is grown for 175 minutes, what will be the cell concentration/mL after 175 minutes?

The correct option is C (32×105cells)
A bacteria divides every 35 minutes. Thus the concentration of bacteria gets doubled in every time period of 35 minutes. In 175 minutes, there will be 5 generations of bacteria (175 minutes / 35 minutes/generation = 5 generations). Thus, when a culture containing 105 cells/ml is grown for 175 minutes the concentration will be 105 x 2⁵ = 32 x 10⁵. So, the correct answer is option C.