I lose many marks on db questions of bio and paper 2 questions of chem. I usually think that my answers are right and complete but they turn out to either be wrong or incomplete. I also feel like some db questions need external knowledge to be answered which are not provided in that chapter. Can you please give me tips on how to answer bio db questions and paper 2 chem question? Also, am I right about needing to know external information in order to answer db questions?