Answer:
17. Laccolith
18. Sill
Explanation:
A laccolith is formed when magma makes its way up a d-ike and lodges itself between sedimentary rocks. The successive flow puts pressure on the rock such that a dome like structure is formed.
Sills are like mini laccoliths but instead are much smaller and linear. They can appear on multiple layers as shown in the diagram above.
An extrusive igneous rock is created when lava hardens.
Answer:
A majority of the Atlantic Coastal plain is flat, there are no hills or mountains in this region of North America. It contains a lot of sedimentary rock and is primarily used in farming/agriculture. This area of land has good access to the sea. This area also features large embayments with drowned river valley's and many wetlands and marshes.
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