Which of the following circular rods, (given radius r and length l) each made of the same material and whose ends are maintained at the same temperature will conduct most heat?

Which of the following circular rods, (given radius r and length l) ea

1.	Which of the following circular rods, (given radius r and length l) each made of the same material and whose ends are maintained at the same temperature will conduct most heat?
Answer» `r=2r_(0),l=2l_(0)` `r=2r_(0),l=l_(0)` `r=r_(0),l=l_(0)` `r=r_(0),l=2l_(0)` ANSWER :B