yes its legal. though not advised if you plan to do it in a densely populated area, some people may get violent over it.
New answer
I've done it. You need to have the right attitude. Kinda like, I dare you to screw with me attitude, if you start to feel threatened. Otherwise, make sure you smile and do not use the women's restroom.
skirts and dresses
They want to keep their hair dry
For some weird reason, it is more socially acceptable. Bras and panties are seen as "erotic" while bikinis are seen as well, swim wear (if you can call it that) even though it basically covers nothing. Girls can wear sports bras in public, but only because its athletic, not "sexy". It's kind of how guys can take their tops totally off in public, but showing your boxers is unacceptable.
the one you can wear in public
YOU CAN if you choose however I would ask permission before I wore someone elses swimsuit. Your not built for a bikini but wear what you like
Nah mate, go nuts
There is no legal bar preventing it.
It's okay to wear nothing but a bikini in public in New York City. It is legal for women to go topless in public in NYC. Some people have said that there is nothing wrong with the female nipple.
In the same way she would wear any other item of clothing.
skirt, shorts, jeans, swim suit, high heels
The Duggar girls wear swimsuits from wholesomewear.com. It is like a wet suit with a loose fitting jumper over it and covers from the neck to the knee. The boys also wear shirts with their swim trunks to be more modest.
A baby should wear at least a swim diaper. There are both disposable and washable varieties available in every size. However, you may also want your baby to weay swim trunks or a bathing suit.