A nylon tennis string on a racket...?

A nylon tennis string on a racket is under tension of 250 N. a) Sketch the situation. b) If its diameter is 1.00 mm, by how much is it lengthened from its un-stretched length of 30.0 cm? c) If the diameter of the string is increased, will the string stretch more, less, or the same. Explain your answer. Enylon = 5 � 109 N/m2