A uniform ladder of weight 250 Newton and length 5 m is placed against a vertical wall. If the angle between the ladder and the ground is θθ, then the force exerted by the wall is:
a) 250cos⁡(θ)
b) 250sin⁡(θ)
c) 250/cos⁡(θ)
d) 250/sin⁡(θ)