You are using a long wrench to loosen a wheel nut. The wrench is located in the x-z plane and the nut is considered the origin of the Cartesian frame. The point of application of the exerted force is located at x = - 1 m, z = 0.25 m from the nut. The applied force in unit-vector notation is given as F = 100 i + 60 k. Determine the position vector r in terms of i and k at the point of application of the force.