A Cu rod 1 cm in diameter and 20 cm long rod is joined at one end to an identical rod of Ni to form a rod 40 cm long with a perfectly sharp interface in the middle. Suppose this couple is heated to 1000 o C and held there for several hours. Sketch profiles of Cu concentration across the interface for t=0 and for three subsequent times. No calculations are needed, simply a welllabeled sketch. B) Suppose an identical couple is made from rods of pure lead and pure tin and heated to 175 o C. Draw a similar set of composition profiles. You should refer to the Cu-Ni and Pb-Sn phase diagrams.