Alyssa wants to know what students think about replacing the candy in two vending machines with more health fu ul snacks. There are 300 sixth graders, 300 seventh graderd, and 200 eighth graders. Half of the students are girls. Alyssa obtains a list of student names, grouped by grade, with the girls listed first in each grade. Alyssa randomly chooses 3 different names of the list of 800 students. What are the chances the first choice is a girl? Second choice is a girl? Third choice is a girl?