I need help on this question.

B. 49 N

Explanation:

Friction Force

When an object is at rest on a rough surface, it encounters a friction force that opposes motion.

The friction force when an object is moving on a horizontal surface is calculated by:

Where is the coefficient of static friction and N is the normal force.  

If no forces other then the weight and the normal are acting upon the y-direction, then the weight and the normal are equal in magnitude:

N = W = m.g

Thus, the friction force is:

We are given the coefficient of static friction and the mass of the object m=10 Kg. The minimum force needed to make it start moving is the maximum friction force:

Fr=0.5*10*9.8

Fr = 49 N

B. 49 N

molecules are free to separate from each other and will take on the shape of the container. molecules move completely at random and high speeds. they vibrate in a fixed position and do not move around much. molecules expand to the edge of their container.