The scale on a map of the United States is 1 cm = 40 mi. If the distance between Albany, NY and Chicago, IL, on the map is 21 cm, what is the actual distance between the cities?

A. 840 miles
B. 804 miles
C. 800 miles
D. 840 cm

PLEASE HELP!!!!!!!

A. 840 miles

21 cm * ( 40 mi / 1 cm ) = 840 mi