Applied Mechanics and Graphic Statics
The following is not a law of static friction:

The force of friction is dependent upon the area of contact
The force of friction always acts in a direction opposite to that in which the body tends to move
The force of friction depends upon the roughness of the surface
The magnitude of the limiting friction bears a constant ratio to the normal reaction between two surfaces

ANSWER DOWNLOAD EXAMIANS APP

Applied Mechanics and Graphic Statics
The following is in unstable equilibrium

A uniform solid cone resting on its base on a horizontal plane
A solid cube resting on one edge
A satellite encircling the earth
A uniform solid cone resting on a generator on a smooth horizontal plane

ANSWER DOWNLOAD EXAMIANS APP