The primary structures of the endocrine system include the adrenal gland, thyroid gland, pineal gland, testis, hypothalamus, ovary, pituitary gland, and pancreas. These glands are essential for hormonal regulation and various bodily functions. The lungs, spleen, and stomach are not part of the endocrine system. ;
A total of approximately 2.81 x 10^21 electrons flow through the device when a current of 15.0 A is delivered for 30 seconds. This is calculated using the formula for electric charge and the charge of an electron. Understanding these calculations helps clarify how electric current involves the movement of many electrons.
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