How to use 'whose' and ' who's'

'Whose/who's bag is this?'

Who's means ‘who is’ - the apostrophe shows that the i is missing:

e.g. "Who's that gorgeous girl in the next row?"

Whose shows the ownership or possession of something by someone and should be followed by a noun

 "Paul, whose eyes are red, hasn’t slept much all holiday."

 Now try and complete the sentences below using whose or who's.

• the owner of a blue Ford?
• mother comes from Spain?
• idea was it to start late?
• your best friend?