Read the excerpt given below and answer the question that follows:

"Our ideas and personality develop only when we are able to freely communicate with others."

(Source: Democratic Politics- I by NCERT)

Mention two Fundamental Duties of the Indian citizens.

Explain the term writ.

Ravi, a social activist, found that his friend, Sunil, had been arrested by the police without being informed of the charges against him. Sunil was not presented before a Magistrate within 24 hours, as law requires. Ravi approached the High Court, seeking Sunil's immediate release, arguing that his detention was unlawful.
Which writ can Ravi file in the High Court to ensure Sunil's immediate release from unlawful detention? Explain the writ in brief.