A student used a stage micrometer scale to calibrate an eyepiece graticule. The diagram shows the student’s combined view of the stage micrometer scale and the eyepiece graticule. The divisions on the stage micrometer scale are $0.1\,\text{mm}$ apart. After removing the stage micrometer scale, the student examined a slide containing blood cells. Because the same lenses were kept in place, the magnification did not change. Using the eyepiece graticule, the student measured the diameter of one of the white blood cells on the slide and found it to be $8$ eyepiece units. What is the correct diameter of this white blood cell in micrometers?
- A$0.2$
- B$0.8$
- C$20$
- D$800$