Is 'To Strike' Separable or Inseparable? - Phrasal Verb Quiz

Quiz for Verb: 'To Strike'

Is the phrasal verb 'To Strike' separable or inseparable in the following examples?

'Strike back' - Attack, take action against someone who has hurt you

'Strike down' - Make someone ill

'Strike up' - Start (conversation, relationship)

'Strike down' - Kill

'Strike upon' - Have a good idea

'Strike up' - Start performing music

'Strike out' - Cross writing out

'Strike out' - Start going towards a place

'Strike down' - Disallow a law, decision, etc

'Strike out' - Fail