PLEASE HELP 7 grade question:(

You are at a restaurant and owe $38 for your meal. you want to leave a 20% tip. how much will your tip be?

Can someone factor this fully? my friend and i have two different answers and i would like to know if either of them is right. you in advance. a^2 - b^2 + 25 + 10a

The students in a class were asked how many siblings they have. the data obtained is represented in the dot plot. the number of students who have no siblings is . the number of students who have three or more siblings is .