The coordinates of the vertices of quadrilateral abcd are a(−5, 1) , b(−2, 5) , c(5, 3) , and d(2, −1) . (the spaces that need to be filled are where the ? 's are.) the slope of ab¯¯¯¯¯ is , the slope of bc¯¯¯¯¯ is , the slope of cd¯¯¯¯¯ is , and the slope of ad¯¯¯¯¯ is . quadrilateral abcd is because choices: -2/7 -1/3 3/2 4/3 a parallelogram a trapezoid neither a parallelogram nor a trapezoid both pairs of opposite sides are parallel only one pair of opposite sides is parallel neither pair of opposite sides is parallel