Fred,Ned,and Ted must make some party hats by folding up pieces of paper.When working alone,they could make ten hats an hour each.If the Ringelmann effect occurs,when Fred works with Ned they will turn out ___ hats an hour each,and when Ted joins them,they will turn out ___ hats an hour each.

A) 12;14
B) 5;1
C) 8;6
D) 4;3
E) 15;20

The Ringelmann effect is a phenomenon where individuals working together in a group put in less effort than when they work independently. Therefore, when Fred and Ned work together, they will not be able to make 20 hats per hour (10 each as individuals) but instead, their productivity will decrease. According to studies, the productivity level of two people working together is around 80% of their individual capacity. Therefore, Fred and Ned will be able to produce 8 hats each per hour (total of 16 hats). When Ted joins them, their productivity will further decrease because the Ringelmann effect gets stronger as groups get larger. Therefore, their productivity level may decrease to around 60% of their individual capacity. This means that they will be able to make 6 hats each per hour (total of 18 hats). Thus, the best choice is C, which states that they will be able to make 8 hats per hour each when working in a pair, and 6 hats per hour each when working as a group of three.