If a wire of resistance $R$ is stretched to double of its length, then the new resistance will be

All the edges of a block in cuboidal shape with parallel faces are unequal. Its longest edge is twice its shortest edge. The ratio of the maximum to minimum resistance between parallel faces is: $(a>b>c)$

A conductor with a rectangular cross-section has dimensions $\left(4a\times 2a\times a\right)$ as shown in the figure. Resistance across $AB$ is $x$, across $CD$ is $y$, and across $EF$ is $z.$ Then, 

In the given figure, the equivalent resistance between the points $A$ and $B$ is

A bridge circuit is shown in the figure. The equivalent resistance between $A$ and $B$ will be: