When Joel and Frank pulled on a rope alone, each exerted a force of 100 pounds. Next, they were asked to pull together. Each is given enough room on the rope to avoid accidental coordination problems. But when they pull together, their combined effort is 160 pounds. This may be due to:

Social loafing

Explanation: Social loafing can be simply defined as the tendency of individuals in a group to provide or contribute less than they will normally provide if they were to work as an individual.

When Joel pulled the rope, he exerted a force of 100, when Frank also pulled the rope, he exerted a force of 100 pound. So one will expect that their combined exertion force will be 200, but working together as a group will require them to provide less individual force than they would have provided if they where to pull the rope individually. This is a good illustration of social loafing.

when your a dog and you need a bone.   go and eat a rabbit

probably 3 since archeologists and historians don’t understand there writing.