Help gaining weight?

I'm 5'6" and 110lbs.

These are my measurements:

34"-26"-36"

According to my BMI, I'm underweight, and I look it. I'm going to try to gain some weight because I hate being this skinny. It's uncomfortable, and I don't like the way it looks.

So I have a few questions:

What is a healthy weight for my height?

What are good measurements for my height?

Guys, what weight do you think looks best on a girl with my proportions?

Thanks :)
Help gaining weight?
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