Final answer:
Emperor Jiaqing faced problems of foreign aggression, opium crisis, and peasant revolts after the death of Emperor Qianlong.
Step-by-step explanation:
After the death of Emperor Qianlong, his successor, Emperor Jiaqing, faced several significant problems. One of the major problems was foreign aggression, especially from the British during the Opium Wars. The Qing empire was weak and struggled to defend itself. Additionally, there were internal issues such as the ongoing opium crisis, crumbling infrastructure, and peasant revolts.