Answer :
If an object is at rest, it means the object is in a state of equilibrum. The net force of an object is a state of equilibrum is zero.
The net force can be said to be the sum of all forces acting on an object.
For an object to be in a state of equilibrum or at rest, the sum of the forces must be equal to zero.
According to Newton's law, the net force of a body at rest of in equilibrum is zero.
Therefore, if an object is at rest, the net force acting on it will be zero.
ANSWER:
Zero.