Physical structures..........
Answer:
A. The magma cooled too quickly too quickly for gas to escape.
Explanation:
Scoria is a type of extrusive igneous rock. Some of their characteristics include that they cool quickly with no time for large crystals to form, some of them have large vesicles which are holes caused by gas bubbles when the lava was molten.
Answer:
<h2>An activated B cell divides into cells that give rise to memory B cells and plasma cells.</h2>
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