present perfect (since or for)

My internet connection hasn't been working _______ the last few minutes.

• for

• since

He's played the piano _______ he was 12.

• for

• since

You've been watching TV _______ over three hours.

• for

• since

Jill hasn't dated _______ her husband left her last July.

• for

• since

She's been promoted twice _______ 2007.

• for

• since

We've been waiting for you _______ 7:00!

• for

• since

We haven't been camping _______ many years.

• for

• since

Jim's been thinking about the problem _______ hours.

• for

• since

I haven't worn high heels _______ my wedding.

• for

• since

They've owned their car _______ a long time.

• for

• since