The resistance is 4 times the resistance of the first wire. the formula is R = p*l/A with p being resistivity, l length and A area. So if you double length and half area, which botv result in more resistance, you get p*2/0.5 or 4 (p can be abandoned because it is the same. We take standard length and area as 1)
My answer is "Watt per square meter".
Explanation:
The given data is as follows.


Electric potential energy (
) = ?
Formula to calculate electric potential energy is as follows.
= 
= 
Thus, we can conclude that the electric potential energy of the pair of charges when the second charge is at point b is
.
Image #3 good luck!!!!!!!!!!!