c.

i.Explain in words how you can use differential calculus to calculate the creep strain rate from a set of data for creep strain as a function of elapsed time. State any standard rules for differentiation that you would need to apply in obtaining your result. Your answer should be no more than 2 0 0 words. You do not need to include equations, but you can include general equations and/or specific examples if it helps with your description.

ii.The equation below is a polynomial of order 4, fitted to the data recorded in a creep test conducted on a particular type of steel, for an elapsed time between 10 to 20 hours.

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