A student draws a force triangle using 1.0 cm to represent 25 N. The resultant arrow is 6.4 cm long and points 35∘ 35^\circ\,35∘ south of east. What additional force would produce equilibrium?
160 N160\ \mathrm{N}160 N, 35∘35^\circ35∘ south of east
40 N40\ \mathrm{N}40 N, 35∘35^\circ35∘ north of west
160 N160\ \mathrm{N}160 N, 35∘35^\circ35∘ north of west
40 N40\ \mathrm{N}40 N, 35∘35^\circ35∘ south of east