Answer:
A unitary government is a system of government that positions all the powers of a State in a Central government. A Unitary system involves dictatorship and totalitarianism. Usually, all rules and regulations guiding the country are made by the Central government. The affairs of the country are overseen by the Central government. Other systems of governments handle a fragment or no powers. Examples of countries with a Unitary system are Spain, Saudi Arabia, Morocco, Barbados, etc.
The Federal government is a system of government that separates the powers of the state between the National and State government to bring about laws that would guide the affairs of the country. For instance, the United States has a Federal system of government with a Constitution specifying the rules guiding the country. With regards the powers shared, the National government can have the overall power over a certain situation but would still retain some space for the States to function in the same capacity.
Con-federal government is different from the two systems of government because the Central government has little powers in the affairs of a state. Based on an agreement between states powers are concentrated on the states and only a few powers are given to the Central government.
In comparison, all the systems of government give powers to central government.