Why do both the buyer and the seller in a solo exchange pursue their own self-interests?

1.because the parties in the transaction do not plan on doing business together again.
2.because both the buyer and the seller have a high level of dependence on each other.
3.because less hassle means more value to the buyer.
4.because the buyer is confident that, over the long run, he or she will get a fair share of the profit.
5.because both believe the other party would not take advantage of them if given the opportunity

You own a nonunion company with 93 nonexempt employees. all of these employ- ees pack books into boxes for shipment to customers throughout the united states. because of wide differences in performance, you have decided to try performance appraisal, something never done before. until now, you have given every worker the same size increase. now you want to measure performance and reward the best performers with bigger increases. without any further information, which of the five types of appraisal formats do you think would be most appropriate? justify your answer. do you anticipate any complaints, or other comments, from employees after you implement your new system?