I] Question 1 0 out of 10 points The stiffness of the aluminium specimen (in GPa), using the class average data is, : load, N 2000 4000 6000 8000 10000 12000 14000 16000 17000 Answer extensome ter units 9 25 43 63 83 105 132 180 280 Selected Answer: 9 62.1 .m Correct Answer: 0 66 Answer range +l 2 (64.0 - 68.0) K7\". Response Feedback: This is the slope of the initial part of the stress - strain curve. Check that you have stress in MPa and that you have converted your extension values to strain. This is done by taking the reading from the dial gauge (each division was 0.01 mm so if division were called out, e.g. 1.5 then you need to divide by 1000, i.e. 0.0015rnrn) Divide this extension by 50 (the gauge length of the extensorneter) On calculating the slope you need to take into account that the curve may not pass through the origin