Thanks soloflyer for your reply.

Further i would answer it as follows.

Political system of Islam is based on certain principles. these principles are equality, consultation, vicegerency, sovereignty of Allah,accountability etc. In each of these principles i would justify how each of these principles contribute to the prosperity of a state. For example, if principle of consultation is applied, people of a state would take decisions by consultation. If people elect their ruler by consultation, this ruler will be a pious and God-fearing who will work for the prosperity of state. Similarly all other principles promote prosperity of a state.

Is this right answer?

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We can trust the man of troubles but not on the man of pleasures.