Determine which lines, if any, must be parallel. Select all that apply. b - O a and b O cand d none Explain your reasoning The lines are parallel by the Linear Pair Perpendicular Theorem. The lines are parallel by the Perpendicular Transversal Theorem. The lines are parallel by the Lines Perpendicular to a Transversal Theorem You need to know something about both of the intersections between the transversal and the two lines