Present perfect since and for

Nobody has seen him --- last Friday.

FOR or SINCE?

It has been cloudy --- some days.

FOR or SINCE?

He has been watching TV ---- hours!

FOR or SINCE?

They've been living in France -- my cousin was born.

FOR or SINCE?

We've had terrible weather --- many weeks.

SINCE or FOR?

I've known my best friend --- a few years.

SINCE or FOR?

We´ve been taking English class with Miss Ale --- August 2016.

SINCE or FOR?

We have been waiting for the bus -- half an hour!

FOR or SINCE?

I've known Tom --- 2001.

SINCE or FOR?

Things have changed --- my friend doesn´t come to school.

SINCE or FOR?

Our dog has been ill --- two days.

SINCE or FOR?

I've been looking for this book --- last week.

SINCE or FOR

I´ve waited --- a long time.

SINCE or FOR?