D as some countries don’t have certain things as other countries have more than they need so they trade the item for another item.
Answer:
The answer is social clock.
Explanation:
This phenomenon explains the expectancy of society to achieve certain things at a determined time (for example, graduating from high school at age eighteen or getting married in your twenties). However, these expectations are variable in different parts of the world.
Bernice Neugarten proposed the idea in order to explain the aging process. She stated that events in people's lives occur in a predictable manner.
Funding for most public universities come from state sales taxes and state income taxes.
Answer:
Islam spread through military conquest, trade, pilgrimage, and missionaries.
Arab Muslim forces conquered vast territories and built imperial structures over time.
Most of the significant expansion occurred during the reign of the Rashidun from 632 to 661 CE, which was the reign of the first four successors of Muhammad.
The caliphate—a new Islamic political structure—evolved and became more sophisticated during the Umayyad and Abbasid caliphates.
Explanation:
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