Assess students' understanding of how coefficients in quadratic functions—standard (ax^2+bx+c), vertex (a(x−h)^2+k), and factored (a(x−r1)(x−r2)) forms—determine a parabola's vertex, axis of symmetry, real roots, and concavity. Questions should require reading features directly from each form, using -b/(2a) and completing the square or converting between forms when necessary, and explaining how variations in a, b, and c affect graph shape, position, and root behavior.