She will fly to Washington,____ is the captal of the USA.A.t

She will fly to Washington,____ is the captal of the USA.A.that B.where C.which D.in which
She will fly to Washington,____ she can enjoy herself.
A.where
B.that
C.which
D./
The story happened on a day ____ the weather was wet and cold.
A.when
B.which
C.in which
D.on when
The story happened on a day ____ was wet and cold.
A.then
B.on which
C.which
D./