A 4-M-Long Ladder (Mass = 56 Kg) Leans Against a Frictionless

Multiple Choice

A 4-m-long ladder (mass = 56 kg) leans against a frictionless wall. The base of the ladder makes an angle of 55º with the rough floor, having $\mu _ { s } = 0.5$ . The frictional force (which is not the maximum frictional force) exerted by the floor that acts on the ladder is

A) 270 N.
B) 240 N.
C) 210 N.
D) 190 N.