Match the following maya, aztec, and inca inventions to the effects they produced.

Rope bridges: Helped the Inca travel long distances and communicate with their neighbors. The Inca were masters of the use of fiber as a material to solve their problems and one of their more renowned creations is the rope bridge. They were able to create incredibly long structures made out of ichu grass, that was woven into large bundles to create bridges that were an integral part of the Inca road system.  

Chinampas: Helped the Aztec farm more productively. Chinampas was a type of agriculture that used small, rectangular areas of fertile land to produce food on the shallow lake beds in Mexico. Also referred to as "floating gardens", it is not originally developed by the Aztecs. This tribe was the first to use this invention as a form of large-scale cultivation.    

Pyramid at Chichen Itza: Helped the Maya view astronomical phenomena such as eclipses with the naked eye. This construction known as Pyramid of Kukulcan or The Castle in Spanish has an astronomical purpose among its many uses. It allowed the Mayans to see the events in the sky without any additional viewing aid and it also worked as an actual solar calendar (Each of the four sides of the pyramid has 91 steps, and adding the final step at the top platform, they total 365, the number of days in their calendar.)

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).