Which one of the following is the length of Panama Canal?

NCERT (2026-27): “The Panama Canal … This canal connects the Atlantic Ocean in the east to the Pacific Ocean in the west. It has been constructed across the Panama Isthmus between Panama City and Colon by the U.S. government which purchased 8 km of area on either side and named it the Canal Zone. The Canal is about 72 km. long and involves a very deep cutting for a length of 12 km.”