Mention the duties of a line judge.

Duties of a line judge: 1. To stand at the corner of the court and signal whether the ball is 'in' or 'out' with a flag. 2. To signal when the ball touches the antenna or crosses the net outside the crossing space. 3. To signal foot faults of the server. 4. To indicate if a player touches the net or an outside object, when the ball is in play, as asked by the referee.