Complete each of the following, so as to make a true statement: (i) A quadrilateral has ______sides. (ii) A quadrilateral has ______angles. (iii) A quadrilateral has ______vertices, no three of which are ______ (iv) A quadrilateral has ______diagonals. (v) The number of pairs of adjacent angles of a quadrilateral is ______ (vi) The number of pairs of opposite angles of a quadrilateral is ______ (vii) The sum of the angles of a quadilateral is ______ (viii) A diagonal of a quadrilateral is a line segment that joins two ______vertices of the quadrilateral. (ix) The sum of the angles of a quadrilateral is ______ right angles. (x) The measure of each angle of a convex quadrilateral is ______ 180∘. (xi) In a quadrilateral the point of intersection of the diagonals lies in ______ of the quadrilateral. (xii) A point is in the interior of a convex quadrilateral, if it is in the ______ of its two opposite angles. (xiii) A quadrilateral is convex if for each side, the remaining ______ lie on the same side of the line containing the side.