A Metal Bar Is Used to Conduct Heat $\degree$ C and at the Other Is 20

Multiple Choice

A metal bar is used to conduct heat. When the temperature at one end is 100 $\degree$ C and at the other is 20 $\degree$ C, heat is transferred at a rate of 32 J/s. The bar is then stretched uniformly to twice its original length. If again it has ends at 100 $\degree$ C and 20 $\degree$ C, at what rate will heat be transferred between it ends?

A) 4 J/s
B) 8 J/s
C) 16 J/s
D) 32 J/s