Determine whether the relation is a function or not. (-2-8). (-1.-4), (1,4),(2,8), (3, 12) function not a function​

Ican figure out 20 shares multiply by $117.98 =2359.6920 shares multiply by $124.32=2486.40then take 40 shares multiply by $128.48=5139.20after that i'm lost any be greatly appreciated.

: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?

Mahnoor randomly selects times to walk into a local restaurant and observe the type of music being played she found that the restaurant was playing country 11 times rock & roll 17 times and blues 8 times use the observed frequencies to create a probability model for the type of music the restaurant is playing the next time mahnoor walks in.