Solve this idk what they want me to do!

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

What is 6/10 rounded to the nearest half

Which of the following is an arithmetic sequence