Are these sentences natural? Jan 13

Hi,

Are the following sentences natural to a native ear?

1. Please decide about a topic you want to talk about in the next meeting.

2. Is it possible for us to get a temporary login to the website?

3. I just saw your twin in the mall (I meant I saw a person looking just like him)

Thanks,
MG.

To my "ear" they sound fine. I've heard people say these very sentences - but that does not make them correct.

To my "eye", however, it's another matter.

You repeat the word "about" twice in the first sentence. I wouldn't do this.
Please decide about a topic you want to discuss in the next meeting.

Is it possible to get us a temporary login to the website?

I just saw your twin in the mall (only if you were inside of the mall). Otherwise, I would say - I just saw your twin at the mall.