The structure shown in the picture is made of copper. the three thin rods are of equal dimensions. the single main rod is heated to 400 °c and then is brought into contact with the rods p, q, and r. after several minutes, the temperatures of rods p, q, and r are recorded. which option gives the correct values of the final temperatures of rods p, q, and r? a) p = r < q b) p = q = r c) p = r > q d) p = q < r