Q$2.$ Consider the following $($incomplete$)$ ER diagram.

HKID

phone$\_$no

name

address

is parent of

$($a$)$ Complete it by clearly marking the participation and cardinality constraints, using reasonable assumptions about people in a city $($e$.$g$.$ Hong Kong$).$

$($b$)$ Using the informal rules for database design, convert the ER diagram to schemas, clearly marking the key and foreign key constraints.