a) Write a Z-matrix for the ethene molecule (N.B. you do not need to provide numerical values for the bonding parameters). (7 marks) b) Give the SMILES string for the following molecule. (5 marks) c) (i) The equations describing bonding using the harmonic potential and Morse potential are given below. Define each of the terms. V(r,harmonic)=21k(rr0)2V(r,morse)=De(1ea(rr0))2 (5 marks) (ii) Sketch each of the potentials given in part (i). (2 marks) (iii) Which of the potential energy functions given in parts (i) and (ii) could be used to describe bond dissociation? Explain your answer. (5 marks) d) Compare and contrast the rigid-structure and flexible-structure molecular docking schemes. (6 marks)