Help me with 9 please. (a and b)

Use the inverse of the function y=x^2-18x to find the unknown value [tex]y = \sqrt{bx + c \: + d} [/tex]

1. if we have 3 babies what is the probability they’re going to be all boys? 2. if we roll 2 die at the same time what is the probability of getting less than 10 on the first roll and a 5 on the second roll 3. if we have 3 babies what is the probability their is going to be 2 girls? 4. if we have 3 babies what is the probability of having no more than 1 girl? 5. it we have 3 babies and then have another 3 babies what is the probability of us having at least 1 boy and then having all girls?

:24% of students in a class are girls. if there are less than 30 students in this class, how many students are there? how many girls are there?