Which explorer looked for a land bridge between russia and north america? 1. vitus bering 2. john meares 3. robert greys 4. captain james hook

a is correct

hope this let me know if it is right

the conditions that made the byzantine empire vulnerable to attacks by the muslin turks were the sack of constantinople by western crusaders, the conquests of the sultanate of rum, presence of rival kingdoms and finally the set up of fiefdoms at the empire which were owned by the ghazis (turkish warriors).