A train traveling from Aytown to Beetown meets with an accident after 1 hr. It is stopped for 21 hr., after which it proceeds at four-fifths of its usual rate, arriving at Beetown 2 hr. late. If the train had covered 80 miles more before the accident, it would have been just 1 hr. late. The usual rate of the train is:
<spanclass=′latex−bold′>(A)</span>20 mph<spanclass=′latex−bold′>(B)</span>30 mph<spanclass=′latex−bold′>(C)</span>40 mph<spanclass=′latex−bold′>(D)</span>50 mph<spanclass=′latex−bold′>(E)</span>60 mph