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12. The vertex of a parabola is at (4, - 12). a) Write a function to define all the parabolas with this vertex. b) A parabola with this vertex passes through point (13, 15). Determine the function for the parabola.it If1 tills situation: 14. A parabolic arch has x-intercepts x = -6 and x = - 1. The parabola has a maximum height of 15 m. a) Determine the quadratic function that models the parabola. b) State the domain and range of the function.11. For each graph, determine the equation of the quadratic function in vertex form. a 48 Ty b) 44 40 6 (0, 36) 36 32 4 28 (3, 2) 2 24 VX 20 -2 2 4 6 8 AONO 2 VX -4 -12 -8 -4 4 8 N -8