Question 3 Short run production decisions are: constrained because all inputs are fixed O constrained because some inputs are fixed while others are variable constrained because all inputs are variable. O unconstrained. Question 4 The law of diminishing marginal returns (also called the law of diminishing marginal productivity) states that O in the short-run the additional output produced from adding additional inputs must always decrease. in the long-run the additional output produced from adding additional inputs must always decrease. in the long-run the additional output produced from adding additional inputs must not change O in the short-run the additional output produced from adding additional inputs must eventually decrease