(a) President of India is referred to as a nominal head of the state because he exercises most of his powers on the advice given to him by the Prime minister and his council. Legislative Powers : 

1. Assenting a bill passed by the houses. 

2. Ordinances need to be passed by the houses or else will become null and void. 

3. Declaration of emergency must be approved by the houses. 

(b) A proclamation of emergency can be made by the President at any time if he is satisfied that the security of India or any part is in danger, or is likely to be in danger either due to war or external aggression or armed rebellion. 

(c) Two Discretionary powers of the President: 

1. He has a very important role to play in the actual working of the Parliamentary system in our country. The oath of office which the President takes in the name of God on assuming his office puts upon him a sacred obligation to be the guardian of the constitution and law. His oath binds him to render service for the well being of the people of India. 

2. In the case of no single party getting a clear majority, a coalition of parties makes its claim to form the Government. The President has to use his discretionary judgement and invite such a leader to head the Government as Prime Minister who can provide a stable Government to the country. His judgement and decision are of crucial importance.