If there is no change in concentration, why is the equilibrium state considered dynamic?

What is the relation between K_P and K_C. Give one example for which K_P is equal to K_C.

When the numerical value of the reaction quotient (Q) is greater than the equilibrium constant (K), in which direction does the reaction proceed to reach equilibrium?

Consider the following reactions,
H₂(g) + I₂(g) ⇌ 2 HI(g)
In each of the above reaction find out whether you have to increase (or) decrease the volume to increase the yield of the product.

Explain how will you predict the direction of a equilibrium reaction.