a)

/DepartmentIV/WETI:[{"id": "165568"}, {"id": "166666"}]

/165568: {"name": "Jakub Zimny", "department": "WETI"}

/166666: {"name": "Jan Kowalski", "department": "WETI"}

/166777: {"name:", "Elżbieta Nowak" "department": "WOiO"}


b)

/DepartmentIV/WETI/-/165568: null
/DepartmentIV/WETI/-/166666: null

/165568/-/name:"Jakub Zimny"
/165568/-/department:"WETI"

/166666/-/name:"Jan Kowalski"
/166666/-/department:"WETI"

/166777/-/name:"Elżbieta Nowak"
/166777/-/department:"WOiO"