According the AA Route Planner (GB Edition) the distance is 80.1 miles, this will take about 1 hours and 35 minutes to drive, assuming you take the direct route and there are no stops, accidents, breakdowns or other hold ups en route.
23 miles
About 14 miles.
About 10 miles.
Dover is in Delaware.
54
about 470 miles
637 miles
It is 162.26 miles.
637 miles
114 miles
The distance from Dover, England to Brisbane, Australia is 10240 miles (16480 km).The distance from Dover, Delaware to Brisbane, Australia is 9550 miles (15370 km).
London to Dover is roughly 76 miles by road - according to Google Earth