I am not exactly sure of the bust measurement. The dress top is more like a halter top. It might better serve as a swimsuit cover up. Since it is a small I would suspect that it's probably around a 32A.
Sorry for not getting back to you sooner. Been busy this weekend with kid stuff. First chance I have had to get on putie. The dress from the underarm seam to the hem is about 26" long. Hope that helps.