A transmission electron micrograph (TEM) is used to study the nuclear envelope of a eukaryotic cell. Under this high magnification, a single nuclear pore has an actual diameter of 120 nm120\text{ nm}120 nm. If the micrograph has a magnification of ×250,000\times 250,000×250,000, what is the width of this nuclear pore's image on the micrograph?
3.0 mm3.0\text{ mm}3.0 mm
30 mm30\text{ mm}30 mm
300 mm300\text{ mm}300 mm
3000 mm3000\text{ mm}3000 mm