)stimulates ovulation as well as the secretion of progesterone from the ovaries during the second hald of the ovarian cycle.

Progesterone

Explanation: Progesterone is a steroid hormone secreted by the ovaries that prepares the uterus for the implantation of a fertilized ovum and subsequent pregnancy. luteinizing hormone surge: Acute rise of LH levels that triggers ovulation and development of the corpus luteum.

answer:

i don't believe the ocean is purple, but it might once have been:

as for the sky, according to nasa:

"sunlight reaches earth's atmosphere and is scattered in all directions by all the gases and particles in the air. blue light is scattered more than the other colors because it travels as shorter, smaller waves. this is why we see a blue sky most of the time."