A certain solder joint on the undercarriage of a city bus is being tested for shear strength. A sample of solder joints was randomly selected, and the shear strength for each was measured (in N)...

A certain solder joint on the undercarriage of a city bus is being tested for shear strength. A sample of solder joints was randomly selected, and the shear strength for each was measured (in N) before (x) and after (y) temperature-cycle stress. The data are given in the following table.