SELECT Country FROM manager WHERE Age  >  50 INTERSECT SELECT Country FROM manager WHERE Age  <  46
Show the countries that have both managers of age above 50 and managers of age below 46.
CREATE TABLE "railway" (
"Railway_ID" int,
"Railway" text,
"Builder" text,
"Built" text,
"Wheels" text,
"Location" text,
"ObjectNumber" text,
PRIMARY KEY ("Railway_ID")
);
CREATE TABLE "train" (
"Train_ID" int,
"Train_Num" text,
"Name" text,
"From" text,
"Arrival" text,
"Railway_ID" int,
PRIMARY KEY ("Train_ID"),
FOREIGN KEY ("Railway_ID") REFERENCES `railway`("Railway_ID")
);
CREATE TABLE "manager" (
"Manager_ID" int,
"Name" text,
"Country" text,
"Working_year_starts" text,
"Age" int,
"Level" int,
PRIMARY KEY ("Manager_ID")
);
CREATE TABLE "railway_manage" (
"Railway_ID" int,
"Manager_ID" int,
"From_Year" text,
PRIMARY KEY ("Railway_ID","Manager_ID"),
FOREIGN KEY ("Manager_ID") REFERENCES "manager"("Manager_ID"),
FOREIGN KEY ("Railway_ID") REFERENCES "railway"("Railway_ID")
);
INSERT INTO  "railway" VALUES (1,"SECR","SECR Ashford","1901","4-4-0","York","1975-7006");
INSERT INTO  "train" VALUES (1,"51195","Wardha-Ballarshah Pass","Wardha","08:54",1);
INSERT INTO  "manager" VALUES (1,"Ben Curtis","United States","2003","45","5");
INSERT INTO  "railway_manage" VALUES (8,1,"2010");