Fill in the blanks.
(i) The perimeter of circle and its diameter vary __P__ with each other.
(ii) If two quantities p and q vary inversely with each other then __Q__ of their corresponding values remain constant.
(iii) When x and y are in indirect proportion and if y doubles then x becomes __R__
A and c , b and d are same.
The length of a rectangular plot is twice its width. If the length of its diagonal is metres, the perimeter of the rectangle is