PLEASE NOTE: We'd prefer you send your answers to workwithus@rrsoft.co rather than post them publicly in another Gist or in comments on this Gist ;-)
Each voter can vote in zero or more referenda. Each referendum has one or more questions, and each question is a yes/no vote. Write the simplest normalized schema to describe this in generic SQL statements or as an entity-relationship diagram. Point out where the indexes would be if you want to quickly know the results of a given referendum question, but you never expect to query a single voter's voting record.
Your client plans to host their web application on AWS. When would you advise (a) deployment in a single availability zone, (b) deployment in multiple availability zones in a single region (c) deployment in multiple regions? What operational difficulty or complexity, if any, is added as you go from (a) to (b) to (c)?