Table: election_results_1930_3
Columns: district
incumbent
party
first_elected
result
candidates

Question: How many districts does william b. oliver represent?
SQL: SELECT COUNT("district") FROM election_results_1930_3 WHERE "incumbent" = 'William B. Oliver'

Question: What is the last year that someone is first elected?
SQL: SELECT MAX("first_elected") FROM election_results_1930_3