Three Boxes Rest Side-By-Side on a Smooth, Horizontal Floor

Multiple Choice

Three boxes rest side-by-side on a smooth, horizontal floor. Their masses are 5.0 kg, 3.0 kg, and 2.0 kg, with the 3.0-kg mass in the center. A force of 50 N pushes on the 5.0-kg mass, which pushes against the other two masses. What is the contact force between the 5.0-kg mass and the 3.0-kg mass?

A) 0 N
B) 10 N
C) 25 N
D) 40 N
E) 50 N