Question: Which spine has 12 issues?
SQL: SELECT "Spine" FROM "2-151686-3" WHERE "Number of issues" = 12.0;

Question: How many issues end on Jan–72?
SQL: SELECT SUM("Number of issues") FROM "2-151686-3" WHERE "End month" = 'Jan–72';

Question: Which masthead ends on Oct–69?
SQL: SELECT "Masthead" FROM "2-151686-3" WHERE "End month" = 'Oct–69';