Stuck on this!

Problem 2: This problem is based on the following isomers of C6H10O2. Identify the compounds that meet the indicated criteria. Compound(s) that lack stereocenters Compound(s) that possess chiral centers Meso compound(s) Compound(s) that are optically inactive Compound(s) that possess a non-superimposable mirror image Compound(s) that possess a carbonyl functional group Problem 3: Find the stereoisomeric relationships between pseudoephedrine and compounds (A) - (D). Choose from the following words to describe the relationship: Enantiomers Diastereomers Different conformations of the same compound (A) (B) (C) (D)