Answer: Roads
Explanation:
All roads lead to Rome, and the Incas had roads to communicate as well, and likewise, the Aztecs built canals and Roads to unite their empire.
The correct answer in the missing blank is known as "separation".
The six degrees of separation is known as a theory in social networking wherein it states that a person can be connected anyone in the world, no matter how far, through a process of acquaintances, which possesses not more than five mediums.
When Sharon Ravitch solved the problem by studying in a professional development program at her own school, it means that she developed new skills that could positively impact her professional life.
A professional development program in schools aims to help develop students' skills and abilities through online training, university studies, coaching and consulting.
Therefore, these programs are very favorable to students for a better career direction and help in the development of multidisciplinary intelligence, making the individual better able to face challenges in social and professional life.
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