Answer :
Final answer:
The Inca developed their road system using mortar to hold the stones together and built stone and earth causeways. These roads connected cities and were also built in less densely populated areas such as the deserts.
Explanation:
The Inca developed their road system using mortar to hold the stones together. They did not use suspension bridges over rivers, but rather built stone and earth causeways that could withstand the challenging terrain. These roads connected cities and were also built in less densely populated areas such as the deserts.
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