A spring has k = 81 N/m. Part A Draw a graph of F vs. x and use it to determine the work needed to stretch the spring from x = 2.3 cm to x = 7.0 cm, where x = unstretched length. Express your answer to two significant figures and include the appropriate units. W = Submit H Value Provide Feedback Request Answer Units Constants Periodic Table ? O refers to the spring's Next >