according to afonso, what have been the detrimental effects of the portuguese presence in his kingdom? 2. what do the letters reveal about the workings of the slave trade in the kingdom? who participated in it? 3. what do the letters reveal about afonso's attitude toward slavery? does he oppose the practice as such or only certain aspects of it? 4. what steps had afonso taken to deal with the problems caused by the portuguese? what do the letters suggest ab