What's your expectation for a response when sending an email?

I’m finding my expectations when sending or receiving emails don’t necessarily match up with others, so I’m hoping you can help me with what’s typical and expected…

Let’s say in a business setting, if you use email fairly often, what are your expectations for the other party?

> How quickly do you expect a response?
> Are you upset if you don’t receive one?
> If the email covers a task, do you expect or want an email confirming they’re working on it? Or just let you know when it’s done?
> If something is important or urgent, do you use email or some other way to get in touch?