By comparing the position of the sun and the shadows cast at noon on the summer solstice in two different cities, Eratosthenes was the first to determine that Earth was round. the distance between the two cities. the distance from Earth to the sun. the size of Earth.

The correct statement is ' the Size of the Earth'.

Explanation:

Most Greek scholars soo many years agreed that the earth was shperical in shape but never knew the size of the Earth.

Eratosthenes was a man of many talents, he was a geographer, a mathematician, an astronomer and a historian. With the expanse of knowledge he had, he compared the position of the sun and the shadows cast at noon on the summer solstice in two different cities. With reasonable accuracy, he was able to determine the shperical size of the earth. He computed this by using simple geometry and trigonometry and by recognizing Earth as a sphere in space.

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 : )

above statement is not a true statement about the open ocean because the open ocean has low levels of nutrients. most of the photosynthetic activity on earth occurs in the open ocean within the photic zone. organisms in the deep ocean are exposed to frigid temperatures and total darkness but it does not begin at the low-tide mark.