By Mrs. Saidatul Radhiah Binti Ghazali, University College Tati
| 1 | Comment from Dr. Arlina Binti Ali | Why HAp added with Mn and Fe |
| 2 | Question from Dr. Hamdi Muhyuddin Barra | Is there a relationship between the HOMO-LUMO energy band gap of the three samples and their UV absorption properties? |
| 3 | Question from Mr. Sunny John A. Lood | Is there any possible increased in the SPF value if Fe and Mn are mix? Thanks |