Answer:
d. may belong to any of the three primary rock types
Explanation:
- Metamorphic rock is the transformation of any of the existing rocks through the process of metamorphism i.e associated with changes in form. When the original rocks are subject to intense heat from below. The Pressure over these rocks causes profound hearing and compaction of rocks particles and matter.
- About 12% of the earth's surface is made up of metamorphic rocks that are either derived from the igneous or sedimentary rocks based on texture, chemical, and mineral assemblage.
- Some common examples of these rocks are gneiss, slate, marble, and schist, etc that have been formed from the sedimentary processes.
The center of the Earth is made up of two layers, the outer core and the inner core. The outer core is the third layer of the Earth. It is the only liquid layer, and is mainly made up of the metals iron and nickel, as well as small amounts of other substances. The outer core is responsible for Earth's magnetic field.
The Presidential election in Nigeria in 1999 was significant
because it is the first election after the 1993 coup and it is the first
election of the Nigerian republic. In this election, Olusegun Obasanjo won over
Olu Falae. 62.78% of votes was casted under Obasanjo.
The U.S. has more than 87,000 dams greater than six feet high (and two million overall). While many dams continue to provide benefits such as flood control, irrigation, and water supply, for other dams the cost of maintenance or the negative effects on communities, fish, and tribes justifies their removal.
Dam owners and regulators decide whether to remove a dam by weighing many factors including: the cost of removal and the ability to replace any lost power generation against avoided long-term maintenance; safety concerns; benefits to endangered fish populations; increased recreational and commercial fishing; and restoration of cultural values of nearby tribes.
By 2020, roughly 70% of dams will be more than 50 years old, inviting us to reconsider the value to the public of long-term investments in this infrastructure.
Answer: Is prone to desertification or drought.
Explanation: The Sahel region is located in Africa between the Sahara to the north and the Sudanian Savanna to the south.
The Sahel has a semi arid climate which is characterized by precipitation below potential evapotranspiration.
What this means is that the amount of water that would be evaporated and transpired by a specific crop or ecosystem is low. This region is prone to desertification or drought because of the low amount of water evaporated and transpirated in the region.
