Question

A piece of wire is redrawn by pulling it until its length is doubled .compare the new resistance with the original value

Answer 1

if the length is doubled then the new resistance will be double the old resistance because the resistance is proportional to the length 
R = r L/A
r - resistivity which depends on material
L - length
A - area of cross section
Note : in reality the area of cross-section decreases when a wire is stretched but in this case i have neglected it. If you want to consider that factor then you should mention Poisson's ratio

Answer 2

Answer:

because the resistance is directly proportional to the length therefore if its length will be doubled then the resistance will be doubled too