fossils have a species of bird are found in layer 3. Which layer is most likely to have organisms that lived at the same time as the bird species ?

not sure if this what   you'r looking for would be percent composition

the menstrual cycle – higher tier. negative feedback mechanisms affect the production of hormones in the menstrual cycle. oestrogen also stimulates the release of lh (luteinising hormone) from the pituitary gland, which in turn controls the production of progesterone.