Find the countries who has the heaviest ships.

create table classes( cclass varchar2(30) primary key, type varchar2(2), country varchar2(30), numguns integer, bore integer, displacement integer );

create table ships( sname varchar2(20) primary key, sclass varchar2(30), launched integer );

create table battles( sname varchar2(30) primary key, bdate date );

create table outcomes( ship varchar2(30), battle varchar2(30), result varchar2(10), constraint outcomes_pk primary key (ship, battle)

);

insert into classes values('Bismarck','bb','Germany',8,15,42000); insert into classes values('Iowa','bb','USA',9,16,46000); insert into classes values('Kongo','bc','Japan',8,14,32000); insert into classes values('North Carolina','bb','USA',9,16,37000); insert into classes values('Renown','bc','Gt. Britain',6,15,32000); insert into classes values('Revenge','bb','Germany',8,15,29000); insert into classes values('Tennessee','bb','USA',12,14,32000); insert into classes values('Yamato','bb','Japan',9,18,65000);

insert into ships values ('California','Tennessee',1921); insert into ships values ('Haruna','Kongo',1915); insert into ships values ('Hiei','Kongo',1914); insert into ships values ('Iowa','Iowa',1943); insert into ships values ('Kirishima','Kongo',1915); insert into ships values ('Kongo','Kongo',1913); insert into ships values ('Missouri','Iowa',1944); insert into ships values ('Musashi','Yamato',1942); insert into ships values ('New Jersey','Iowa',1943); insert into ships values ('North Carolina','North Carolina',1941); insert into ships values ('Ramillies','Revenge',1917); insert into ships values ('Renown','Renown',1916); insert into ships values ('Repulse','Renown',1916); insert into ships values ('Rasolution','Revenge',1916); insert into ships values ('Revenge','Revenge',1916); insert into ships values ('Royal Oak','Revenge',1916); insert into ships values ('Royal Sovereign','Revenge',1916); insert into ships values ('South Dakota','Tennessee',1921); insert into ships values ('Tennessee','Tennessee',1920); insert into ships values ('Washington','North Carolina',1941); insert into ships values ('Wisconsin','Iowa',1944); insert into ships values ('Yamato','Yamato',1941);

insert into battles values ('North Atlantic','10-MAY-1924'); insert into battles values ('Guadalcanal','15-NOV-1942'); insert into battles values ('North Cape','26-DEC-1943'); insert into battles values ('Surigao Strait','25-OCT-1944');

insert into outcomes values ('Bismarck','North Atlantic','sunk'); insert into outcomes values ('California','Surigao Strait','ok'); insert into outcomes values ('Duke of York','North Cape','ok'); insert into outcomes values ('Fuso','Surigao Strait','sunk'); insert into outcomes values ('Hood','North Atlantic','sunk'); insert into outcomes values ('King George V','North Atlantic','ok'); insert into outcomes values ('Kirishima','Guadalcanal','sunk'); insert into outcomes values ('Prince of Wales','Guadalcanal','damaged'); insert into outcomes values ('Prince of Wales','North Atlantic','damaged'); insert into outcomes values ('Rodney','North Atlantic','damaged'); insert into outcomes values ('Scharnhorst','North Cape','sunk'); insert into outcomes values ('South Dakota','Guadalcanal','damaged'); insert into outcomes values ('Tennessee','Surigao Strait','ok'); insert into outcomes values ('Washington','Guadalcanal','ok'); insert into outcomes values ('West Virginia','Surigao Strait','ok'); insert into outcomes values ('Yamashiro','Surigao Strait','sunk');