What material were books written on in the islamic world, making them relatively cheap and accessible? 18.what were the christians of al-andalus known as?

What was zheng he’s most important accomplishment? zheng he spread chinese ideas and brought wealth to china from his travels. zheng he commanded an impressive fleet of ships. zheng he sailed the indian ocean and around africa. zheng he conquered lands as far away as africa to increase the dynasty’s power.