Final answer:
Compound a, compound b, and compound c are all amines. The structures for isopropyldimethylamine and dipropylamine are provided.
Step-by-step explanation:
Compound a, compound b, and compound c are all amines. Amines are organic compounds that contain a nitrogen atom bonded to three different substituents. In the case of isopropyldimethylamine, the structure would look like this:
For dipropylamine, the structure would be:
As for compound d, the common name for the amine would depend on its structure, which is not provided in the question.