Which of the following studies would a community ecologist undertake to learn about competitive interactions? i) selectivity of nest sites among cavity-nesting songbirds ii) the grass species preferred by grazing pronghorn antelope and bison iii) stomach analysis of brown trout and brook trout in streams where they coexist

the corpus luteum secretes estrogens and progesterone. the latter hormone causes changes in the uterus that make it more suitable for implantation of the fertilized ovum and the nourishment of the embryo. if the egg is not fertilized, the corpus luteum becomes inactive after 10–14 days, and menstruation occurs.

i hope this : )

igneous rocks which formed by the crystallization of magma at the surface of the earth called extrusive rocks. they are characterized by fine-grained textures because the rapid cooling at or near the surface did not provide enough time for large crystals to grow.

is it multiple choice?