Consider the universal relation R = {A, B, C, D, E, F, G, H, I, J} and the set of functional dependencies G = {{A, B} - > {C}: {B, D} - > {E, F}: {A, D} - > {G, H}: {A} - > {I}: {H} - > {J}}. a) What is the key for R? (Show all your steps) b) Normalize R up to 3NF. (Show only your final answer)