Psychology review: 11. An executive in a stockbrokerage firm works with his office door closed. At the same time every hour he opens the door to see what his employees are doing. The employees have learned to work only during the five minutes before he opens the door. Their work pattern is typical of responses that are reinforced on a schedule.
A. fixed-ratio
B. fixed-interval
C. variable-ratio
D. variable-interval

In financial aspects, a depression is a sustained, long haul downturn in monetary movement in one or more economies. it is a more extreme monetary downturn than a recession, which is a slowdown in financial action through the span of a typical business cycle. a depression is an irregular and extreme type of recession. so depression is always followed by recession but it is not correct to state that a depression always follow a recession.