[PAR] [TLE] The Sensorium [SEP] The Sensorium is regarded the world's first commercial 4D film and was first screened in a Six Flags theme park in Baltimore in 1984.  It was produced in partnership with Landmark Entertainment. [PAR] [TLE] Six Flags [SEP] Six Flags, officially Six Flags Entertainment Corporation, is an amusement park corporation based in the United States, with properties in the US, Canada, and Mexico.  It is the largest amusement park company in the world, based on the number of properties owned, and is ranked sixth in terms of attendance.  The company maintains twenty properties throughout North America including theme parks, thrill parks, water parks, and family entertainment centers.  In 2016, Six Flags properties hosted over 30.1 million guests.
[PAR] [TLE] The Sensorium [ SEP ] The Sensorium is regarded the world 's first commercial 4D film and was first screened in a Six Flags theme park in Baltimore in 1984 . It was produced in partnership with Landmark Entertainment . [PAR] [TLE] Six Flags [ SEP ] Six Flags , officially Six Flags Entertainment Corporation , is an amusement park corporation based in the United States , with properties in the US , Canada , and Mexico . It is the largest amusement park company in the world , based on the number of properties owned , and is ranked sixth in terms of attendance . The company maintains twenty properties throughout North America including theme parks , thrill parks , water parks , and family entertainment centers . In 2016 , Six Flags properties hosted over 30.1 million guests .
How many properties are maintained by the amusement park corporation that first screened the film The Sensorium in 1984?
How many properties are maintained by the amusement park corporation that first screened the film The Sensorium in 1984 ?
twenty
twenty