The Correct choice is : C. <u>Solids</u>
Sound waves need a medium to propagate, and the most suitable medium for that is solids, where it travel the fastest or with greatest efficiency.
Along with the fact that the infrastructural and industrial levels of the African colonies was never really developed by Europeans, the many various and opposing ethnic groups had no one to keep them in check now. As a result many civil wars took place between different religions, specific religious denominations, and specific ethnic groups of said religious denominations. Also nearly all of the leaders that broke free of European rule were woefully unprepared to lead a country both governmentally and economically. All of these factors are what lead to Africa's current problems.
Answer:
7
Explanation:
because there are 7 cars. try to see if this helps
It has a big impact on the tides because of gravity
