Starting UML for Room:

Room
------------------
+ name : String
+ length : double 
+ width : double
------------------
+ calculateArea() : double
+ calculatePerimeter() : double

NOTES:
Members with + sign are public: For now, make everything public.
area = length * width
perimeter = length * 2 + width * 2

𝗨𝗽𝗱𝗮𝘁𝗲𝗱 𝗩𝗲𝗿𝘀𝗶𝗼𝗻 𝗰𝗿𝗲𝗮𝘁𝗲𝗱 𝗯𝘆 𝘁𝗵𝗲 𝗲𝗻𝗱 𝗼𝗳 𝘁𝗵𝗲 𝗹𝗲𝘀𝘀𝗼𝗻:
NOTE: in UML, static/class members are underlined.

Room
------------------
+ name : String
+ length : double 
+ width : double
+ s͟t͟a͟n͟d͟i͟n͟g͟L͟i͟m͟i͟t : d͟o͟u͟b͟l͟e
+ s͟i͟t͟t͟i͟n͟g͟L͟i͟m͟i͟t : d͟o͟u͟b͟l͟e
------------------
+ Room()
+ Room(name : String)
+ Room(name : String, length : double, width : double)
+ calculateArea() : double
+ calculatePerimeter() : double
+ displayRoom() : String
+ maxStanding() : double
+ maxSitting() : double