Chapter 20, Problem 61P

The data below were obtained from a creep test performed atroom temperature on a wire composed of 40% tin, 60% lead, andsolid core solder. This was done by measuring the increase in strainover time while a constant load was applied to a test specimen. Using a linear regression method, find (a ) the equation of these line that bestfits these data and (b ) the $r^2$ value. Plot your results. Does the line passthrough the origin-that is, at time zero-should there be any strain?

If the line does not pass through the origin, force it to do so. Does thisnew line represent the data trend? Suggest a new equation that satisfies zero strain at zero time and also represents the data trend well.