It's probably because there is no gravity which ballpoint pens need for inkflow to the tip.
        
             
        
        
        
V = d ÷ t --> bc d=vt 
V = (76+54)÷(2+5) = 130÷7 = 18.57km/hr
        
             
        
        
        
Explanation:
"Static friction is a force that keeps an object at rest. It must be overcome to start moving the object."
(556 x 0.68) = static friction of 378.08N. before movement occurs.
The  forces (a) and (b) will not move it.  
Each will incur a frictional force preventing movement equal to itself, = 222N. and 334N. respectively.
Forces (c) and (d) will move it, and accelerate it.
Forces (c) and (d) will both encounter friction of (556 x 0.56) = 311.36N. when the cabinet is moving.
 
        
             
        
        
        
A system that repeats to and from its mean or rest point. that executes harmonic motion. a few examples I've heard of are since the springtime a mass-spring system,a swing, simple pendulum, one more example is a steel ball rolling in a curved is this what you need or do you need three more sentences dish. to get S.H.M a body just displaced away from the resting position and of course then is released. the human body oscillates due to the reinforce that pulls it back do you need anything else answered on this and I'll answer it