Answer:
Answer is Sinoatrial node, SA.
Explanation:
The sinoatrial node, SA, is known to be a group of cells which are found at the top of the heart.
The electrical signal that is initiated by the sinoatrial node bring about or stimulates the atria and then the ventricle of the heart.
It should be noted that, the sinoatrial node are regarded as the pacemaker cells.
Answer is B. Antarctic
71 % of the Earth is cover with water. The large water body is divided and have specific names. There are four distinct oceans. These are Pacific, Indian Atlantic and Arctic oceans. Among these Pacific, Atlantic and Indian are the major oceans. The United States along with most countries now recognize the Southern (Antarctic) as the fifth ocean.
Answer:
Your answer is A, Rain forest.
Explanation:
Soils develop faster in warm, moist climates and slowest in cold or arid ones. Rainfall is one of the most important climate factors in soil formation.
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