Because they did not have the right equipment
Answer:
Economic and environment issues are most challenging for developing countries.
Explanation:
For a developing country, the issues of economic and employment are the most dangerous and challenging as the growth of all the other factors depends on this.
Economic and employment related issues can hamper the growth of the citizens which can further result in the slow development (growth) of the nation as well.
If the people of a developing country are not able to get the jobs it simply means that they are not creating per capita income for the income and thus putting the burden on the economy which is not a good for a developing country.
It could be considered a social system because of the way it is organized. First of all, it might present cultural fusion, that is to say; religion, technology, etc are key elements for its functioning. Then, people who work in the trade road need a language. There can be found a misture of culture due to the amount of people working in this system. As regards religion, it might be said that the Silk Road helps to its expansion and spreading.