An NGO $($defined by NGOID$),$ works with many organisations. These organisations can include; political, educational, medical and$/$or financial organisations. Political organisations have a specific political contact, whilst educational organisations are most concerned with certification. An organisation is defined by OrganisationID and Mission. A medical organisation comprises; Doctor, Nurse and Specialist at the very minimum. There is no overlap between roles. The NGO also hires many staff. Staff are categorised as follows; Admin, PR and Finance. Other roles will be introduced in the medium term. Staff are typically defined by name, contact and ID$.$ Due to problems attracting the right staff, Admin can take on the role of PR$,$ skills permitting. The finance staff can sometimes liaise with the financial organisation. A financial organisation holds specific information related to tax code and tax law. It has also been noted that staff can mentor many other staff, or just one fellow staff member. Meanwhile, a financial organisation can liaise with many finance staff. As staff are encouraged to work abroad, they can work in different continents. A continent can have many staff from the same NGO working there. When we refer to continent, in this case, we mean; Asia, Africa and Europe. There are plans to also work in America at some later point. A continent in our database is defined by contact, currency and ID$.$ Our Asia and Africa relations hold information on vaccines. There are many relevant vaccines. Europass is only relevant in Europe. $(16$ marks$)$ b$)$ Explain the Three Schema Architecture for organizing the components and layers of a database system. Refer to schema, immunity and independen