CREATE TABLE "times_of_over_north_america" (
  "event" text,
  "pdt_7_utc" text,
  "mdt_6_utc" text,
  "cdt_5_utc" text,
  "edt_4_utc" text
);

Question: What time is CDT when EDT is 4:55 a.m.?
SQL: SELECT "cdt_5_utc" FROM "times_of_over_north_america" WHERE "edt_4_utc"='4:55 a.m.';

Question: What is the time for PDT when CDT is 6:38 a.m.?
SQL: SELECT "pdt_7_utc" FROM "times_of_over_north_america" WHERE "cdt_5_utc"='6:38 a.m.';

Question: What time is CDT when PDT is 3:17 a.m.?
SQL: SELECT "cdt_5_utc" FROM "times_of_over_north_america" WHERE "pdt_7_utc"='3:17 a.m.';

Question: What time is MDT when EDT is set and PDT is 6:00 a.m.?
SQL: SELECT "mdt_6_utc" FROM "times_of_over_north_america" WHERE "edt_4_utc"='set' AND "pdt_7_utc"='6:00 a.m.';