Pls help me with this question

Monica build a remote control toy airplane for science project to test the plane she launched it from the top of a building the plane travel a horizontal distance of 50 feet before landing on the ground a quadratic function which models the height of the plane in feet relative to the ground at a horizontal distance of x feet from the building is shown

: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?

Which coefficient matrix represents a system of linear equations that has a unique solution ? options in photo*