Describe the law of diminishing returns to variable proportions ? How this law is different from the law of decreasing returns to variable proportions ? Identify which of the following are increasing , decreasing or constant returns to scale production functions : ( i ) Q – AKL2 , ( ii ) Q – AK0.5L0.4, ( iii ) Q – AK 0.4 L0.6 , ( iv ) Q - 50KL0.5 .