CREATE TABLE "baldwin_locomotive_works" (
  "prr_class" text,
  "builder_s_model" text,
  "build_date" text,
  "total_produced" real,
  "wheel_arrangement" text,
  "service" text,
  "power_output" text
);

Question: What is the build date of the model with PRR Class brs24?
SQL: SELECT "build_date" FROM "baldwin_locomotive_works" WHERE "prr_class"='brs24';

Question: How many total units were built of Model ds-4-4-660 with a b-b wheel arrangement and a PRR Class of bs6?
SQL: SELECT SUM("total_produced") FROM "baldwin_locomotive_works" WHERE "wheel_arrangement"='b-b' AND "prr_class"='bs6' AND "builder_s_model"='ds-4-4-660';

Question: What is the build date of the model with a PRR Class of brs24?
SQL: SELECT "build_date" FROM "baldwin_locomotive_works" WHERE "prr_class"='brs24';