A student was informed that a diagram of a bacterial cell had been enlarged 30 000 times. The diagram measured $45\text{ mm}$ in length. What was the bacterium’s actual length?
- A$0.15\text{ mm}$
- B$1.5\,\mu\text{m}$
- C$0.66\text{ mm}$
- D$0.66\,\mu\text{m}$