Can a 30 year old date a 16 year old in Iowa?

Yes. Once a person reaches the age of consent (16) in Iowa, they can consent to sexual activities with anyone older than them.

Can a 16 year old be with a 30 year old?

This means that its against the law for someone to have sex with someone under the age of 16. It wouldnt be illegal for someone whos 16 to have a relationship with someone who is 30 - unless that person is their teacher or in a position of authority. So it would be up to that person to decide whats right for them.

Can a 16 year old date a 28 year old?

Why would you want to date a minor when you are 28? That being said, there is nothing illegal about it as long as there is no sexual contact, which is basically any physical contact with private areas.