Answer:
negative marginal returns 
Step-by-step explanation:
A restaurateur spends $61 on labor and materials to produce 8 meals. By increasing these costs to $78, he can produce 14 meals. By increasing costs to $95, he can produce 20 meals. In terms of capital and labor, he has _____. 
 
decreasing marginal returns 
 
constant marginal returns 
 
[negative marginal returns ]
 
increasing marginal returns