Write an equation that expresses the following relationship. W
varies directly with the cube of u and inversely with d
In your equation, use k as the constant of proportionality.

d, if the egg is not fertilized

Explanation:

The level of hormones remains elevated when fertilization has taken place and the embryo is required to be implanted over the wall of the uterus. The increase in progestrone and estrogen levels causes the endometrium wall of the uterus to be thicken, the progesteron release also makes the mucus of the cervix to be thicken so that the sperms and bacteria remain prevented from entry inside the uterus.  

In the absence of fertilization the level of hormones remain low. The corpus luteum degenerates after 14 days, menstrual cycle begins and the level of estrogen and progesteron remains low.