Auniform ladder of length l and mass m1 rests against a frictionless wall. the ladder makes an angle θ with the horizontal.(a) find the horizontal and vertical forces the ground exerts on the base of the ladder when a firefighter of mass m2 is a distance x from the bottom. (answer using m1, m2, θ, gravity g, l, and x as necessary.) horizontal horizontal force= vertical force= (b) if the ladder is just on the verge of slipping when the firefighter is a distance d from the bottom, what is the coefficient of static friction between ladder and ground? μ =