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Answer:The left ventricle
Explanation:The left chamber of the heart, precisely the left ventricle has the thickest wall because it is known as the MAJOR pump of the heart since it pumps at higher pressure
Some of the reasons can be:
If you're a pre-teen or a teenager who has only started menstruating, you may find that it takes a while for your period to settle in and become regular.
I couldn't think of anything else, but hope this helped enough!
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