Find the one mistake in each sentence and then correct it

Find the one mistake in each sentence and then correct it:

1. She asked me if i knew whow had got the job.
2. I've been meaning to ask you where you get your hair to cut.
3. There were 500 passenger, whose 121 drowned.
4. She was only twenty when she having her first bady.
5. To see if you can guess which one is me in my old school photo.