Secondary reinforcers are learned or conditioned. An example of a secondary reinforcer is grades or money. Secondary reinforcers are learned and are reinforced by the continual use of the reinforcer. Primary reinforcers are biological and include food, drink, and pleasurable activities.
The correct answer is letter D. Social Security is applied to all wages up to $106,800. Medicare, on the other hand, is applied to all wages without limit. That is the relationship between Social Security and Medicare.
B is the first one D is the last on that should be it
The correct answer is A. Reunifying several kingdoms
Explanation:
The Song Dynasty included around nineteen emperors who ruled China from the 10th century to the 13th century. This dynasty is recognized due to its multiple advancements in terms of government and culture. Indeed, during this dynasty, national paper money began to be used as part of the economy and a centralized government was established. This political change unified many kingdoms or territories in China as these were under the rule of the same emperor and share different elements including the use of the same currency.
