Define Observational study

What is the advantage of developing criteria for assessing the effectiveness of business products and processes? a. assessment criteria are answers. b.assessment criteria are inexpensive. c.assessment criteria provide you with a list of relevant things to measure. d.assessment criteria provide you with a list of people to contact to learn more about process mentoring.

Can someone me ? i’ll mark the best answer brainliest : )

During which of the following phases of the business cycle does the real gdp fall? a. trough b. expansion c. contraction d. peak