nefarious yeets answered In what circumstances do you say hello to a…

In what circumstances do you say hello to a stranger?

At work as people approach me. I'd rather say, "what's up?" but that illegal
When a stranger says "hello" to me
When I decide to live on the wild side and answer calls from unknown numbers
When a child is staring at me for an extended amount of time at close range, and I assume they want me to acknowledge them.
When I need someone who works somewhere to do a thing for me.
Any time the stranger is a squirrel that I can see
When I accidentally make eye contact with someone while waiting in a line