For anyone else struggling with the quiz minigame on floor 3, here are some of the answers. Pretty sure I missed one or two, but this should help enough.
What is the name of the town? - City of Sinus
What is the last line on the knowledge of HOP members? - Everyone get along
Executive promoted from a general member? - Livy
What is the minimum cup size required to join HOP? - H-cup
How many members in the headquarters? - 300
What is Bell-sama's favourite food? - Macaroons
On what floor is the seasoning stored? - 6F
What is the effect of the bathhouse's 'Pink Happy Onsen? - Bust size increase
How many stores are there on the restaurant floor? - 27
Btw, you get a hop cube from clearing the quiz.