Scientists found stone tool specimens in a cave in africa. using potassium–argon radiometric dating, they discovered that the tools contained 25 percent radioactive potassium-40. how old are the tools? (you must show your calculations to receive credit.) *the half-life for potassium-40 to argon-40 is 1.25 billion years.

the correct answer would be 6 feet.

"menstrual cycle is a complex cycle that consists of several processes. order of occurrence of steps in menstrual cycle are as follows:

1. high progesterone levels maintain the endometrium lining of the uterus.

2. endometrium lining breaks down and low levels of estrogen stimulate the pituitary to release fsh and lh.

3. fsh and lh stimulates the follicles to develop and the oocyte to produce estrogen.

4. rising estrogen levels suppress fsh production and development of other follicles.

5. a spike in lh causes follicle to rupture.

6. a breakdown of corpus luteum causes progesterone level to drop."