The ohio river is the answer
<span> sediment formed from the weathering and erosion of rock. Over time, sediment accumulates in oceans, lakes, and valleys, eventually building up in layers and weighing down the material underneath. This weight presses the sediment particles together, compacting them. Water passing through the spaces in between the particles helps to cement them together even more. This process of compacting and cementing sediment forms sedimentary rock</span>
Israel's use of scientific methods to increase the productivity of it's land allows the country to Grow almost all of it's own food.
The answer is National security because the citizens need to know that they are being protected, and usually also how they are being protected. But the government often needs so measure of secrecy in order to protect National Security. If the government were to tell citizens exactly how they were being protected and someone posted it onto the internet it would severely compromise that protection. However people do not generally seem to understand that and tensions become heated between the two groups. Both sides reasons are perfectly legitimate, but one outweighs the other by knowledge. The answer is B.
It changed so much because there were always European explorers heading out on voyages, for many reasons (like to trade with neighbouring countries, ferrying people from one land to the other, etc). During those voyages they found new lands, and so the maps had to be revised quite often because of these new discoveries.
