A student creates a poster for an inter-school competition with the title as "WELCOME" in the shape of a parallelogram \(ABCD\).
Based on the above scenario, answer the following questions
(i) If \(\angle A = 2r+6\) and \(\angle C = 4r+2\), then find the value of \(r\)?
(ii) Which condition is used in the above condition to solve for \(r\)?
(iii) If one angle of the parallelogram is \(90^\circ\), then what is the type of quadrilateral thus formed?
(iv) If \(\angle A = 88^\circ\), then the measure of \(\angle D\) is __________\(^\circ\)