11) What is the oldest underground railway in the world?
12) In what US city was the first subway system opened?
13) What color is used to identify express trains on the New York Subway?
14) What is the name of the busiest subway station in New York?
15) How many lines does the Beijing Subway have?
16) What year did the Shanghai metro open?
17) What was the original name for the Subway sandwich chain?
18) What is Subway's slogan?
19) In which year did Subway open its first restaurant?
20) What is the most popular sandwich choice at Subway?