Problem on reversible and irreversible process

Question

The second law states that
 dS ≥ (dQ/T)
, where dS = dQ/T for a reversible process and dS > dQ/T for an irreversible process.  

a. Show that since dW₁₂ = -dW₂₁ (dW_reverse = -dW_forward) for a reversible process, then dQ₁₂ = TdS₁₂
 
b. An egg, initially at rest, is dropped onto the floor. Prove that this process is irreversible. You can assume that the egg returns to its initial temperature after it breaks.