(1) Rate of disappearance of A = Rate of formation of D.
(2) Rate of formation of $C = \large\frac{2}{3} \times $ Rate of disappearance of B
(3) Rate of formation of $D.= \large\frac{1}{3}\times $ Rate of disappearance of B
(4) Rate of disappearance of $A = 2 \times $ .Rate of formation of C.