<image>As shown in the figure, the lower right corner of the quadrilateral paper $$ABCD$$ is folded inward to form $$\triangle PC′R$$, where $$∠B=120^{\circ}$$ and $$∠D=40^{\circ}$$, such that $$C′P \parallel AB$$ and $$RC′ \parallel AD$$. Then, $$∠C =$$ ______.