1. Wingma(e)n confirm they will go for the same type of target as you have targetted and prioritize. Note: as good as this may sound in theory, don't expect all that much from your wingman
2. It's hard to tell sometimes. With RGM you will hear the RWR tone. To be safe, in case you are unsure: Always drop chaff as early as possible, and flares a bit later on, when you have visual ID on the incoming missile in F5. Always: Better safe than sorry, so don't save your F&C !
Hope this helps.