At puberty, the hypothalamus secretes gonadotropin-releasing hormones (GnRH), causing the secretion of gonadotropins by the pituitary gland. These hormones cause the ovaries to produce estrogen and testes to produce testosterone. As the levels of these hormones rise, they shut down the release of GnRH and the gonadotropins. This example illustrates the

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.

they had the law tat factories that produces smoke cannot be built near residential buildings.

building of proper sewage system was done to ensure that the waste is carried away from the humans so that they do not get diseases from it.

also they built water systems to provide water in those areas which are drought prone.

"it built up in the atmosphere"

i think thats it, idk, i tried looking for this exact q& a for grad. and idk if i got this question right or sorry if im wrong