Resilin is a rubber-like protein that helps insects to fly more efficiently. The resilin, attached from the wing to the body, is relaxed when the wing is down and is extended when the wing is up. As the wing is brought up, some elastic energy is stored in the resilin. The wing is then brought back down with little muscular energy, since the potential energy in the resilin is converted back into kinetic energy. Resilin has a Young's modulus of 1.7 × 106 N/m2.
(a) If an insect wing has resilin with a relaxed length of 1.0 cm and with a cross-sectional area of 1.0 mm2, how much force must the wings exert to extend the resilin to 4.0 cm?
(b) How much energy is stored in the resilin?