The Powerbook 100 model has what processor?
CREATE TABLE "list_of_macintosh_models_grouped_by_cpu_" (
  "processor" text,
  "model" text,
  "clock_speed_m_hz" real,
  "l1_cache_bytes" text,
  "introduced" text,
  "discontinued" text
);
SELECT "processor" FROM "list_of_macintosh_models_grouped_by_cpu_" WHERE "model"='powerbook 100';