Can I keep an I phone that I found?

I found this chicks iphone, I already have one and decided to give it back to her. The issue is that I wanted a $200 reward and she said no. She said no reward because it doesn't belong to me and threatened to call police. She don't have my name or number and she was calling me on her own phone. I cut the phone off and haven't had it on for days now. At this point I'm keeping the phone.

Is there a virus on my iphone 6s?

I have an iphone 6s and it's fairly new (hasn't reached its one year mark yet) and there are no problems whatsoever until i go on safari. Occasionally pop ups like "congrats you've won $100000" or "is your phone effected by malware" appear and everytime i close the pop up it would appear again 5 seconds later. I'd have to close the page to get the pop ups to disappear. It's annoying but tolerable… Is it a virus? This didn't start to happen until a month ago

Are there any ways to increase iPhone 6S+ storage?

I've deleted just about everything I can on my 16 GB phone to clear up space for music. I already have an app to store all my photos so they don't take space up and I constantly clear out messages so they don't either.
I was wondering if there was something where I could add storage to my phone where I can keep more than the 16 GB worth of music right in my library so I don't use data to listen to it.
I've read about external storage devices for iPhones but I don't know if they act as a backup or if they actually add storage as well.

Dropped iphone in water?

I dropped my iphone in water, it wasn't in there for very long though. Maybe 5 seconds. I took it out, took the case off and dried it off. It is working perfectly fine, do i need to put it in rice?

Added (1). it is an iphone 6s

I can't delete albums in my photo gallery?

So I imported some videos from my Macbook to my iPhone 6s+ (if the model helps) and I wanna delete those videos because I no longer need them. The thing is, I can't delete them? They're in an album called "Last import" and "Last 12 months". Every time I try deleting them, there isn't an option to delete the videos or the album at all. Please help? What do I do to delete these videos and album?