Answer:
There are three elements . They are 1,{1},{1,{1}}. Definition of set says that it should be collection of “well defined” objects.
The Abdominopelvic cavity Hope this helps :)
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It was commissioned in 1632 by the Mughal emperor Shah Jahan (reigned from 1628 to 1658) to house the tomb of his favourite wife, Mumtaz Mahal; it also houses the tomb of Shah Jahan his self
It’s ADH
Antidiuretic hormone (ADH) is a chemical produced in the brain that causes the kidneys to release less water, decreasing the amount of urine produced.