Ethan pushes a wooden box across a carpeted floor. then he pushes the same box across a smooth marble floor. why does ethan find it easier to push the box on the marble floor than on the carpeted floor?

Because there is less friction on the marble floor.

The  grandmother cell  is a hypothetical  neuronthat represents a complex but specific concept or object.[1]  it activates when a person "sees, hears, or otherwise sensibly discriminates"[2]  a specific entity, such as his or her grandmother. the term was in use at least as early as 1966 amongst staff and students in the department of experimental psychology, university of cambridge, england. a similar concept, that of the  gnostic neuron, was proposed two years later