The period between 28 days and 54 days after conception is considered __ for the development of limbs in an embryo:

stratosphere: as the altitude increases, the air temperature increases. the stratosphere has a layer of ozone, called the ozone layer. this layer absorbs most of the ultraviolet radiation from sunlight. this results in the stratosphere being warmer.

i thinking chemical change

d. groundwater flows through the subsoil and deposits minerals.