What is the main case of the islamic worlds hardship in the thirteenth century a. mongol tribes invaded muslim lands b. western europeans invaded muslim lands c. famine and diseases introduced for africa d. dissension between rival factions of islam

The appropriate answer is b. Mongol tribes invading Muslim lands. The Mongol tribes had been empowered Genghis Khan and as such had become a formidable hoard of conquerors that had seized much of the Eurasian landmass and the ruling Islamic caliphate in the west. The hardships during this period marked the end of the Golden age of Islam.  

zheng he was a chinese explorer who lead seven great voyages on behalf of the chinese emperor. his seven total voyages were diplomatic, military, and trading ventures, and lasted from 1405 – 1433. however, most historians agree their main purpose was to promote the glory of ming dynasty china.

explanation:

one of the main reasons was definitely slavery. back in 1861, republican abraham lincoln was elected and ended up being a major influence in the slavery business. slavery greatly affected the texas economy because back in 1845 during the annexation of texas, slaves became a big part of the texas population. many texans that were in favor of the secession influenced groups through party ties.