Why is a system’s work output limited? a. entropy decreases with each stage of a system, causing a decrease in available entropy to carry out each stage. b. systems tend to become less randomized over time, which causes spontaneous processes to no longer occur. c. energy is destroyed in each stage, causing the amount of available energy to decrease with each stage. d. energy is lost as heat in each stage, causing the amount of energy available to decrease with each stage.

the answer to this question is D. -Energy is lost as heat in each stage, causing the amount of energy available to decrease with each stage

i'd say that the moon rock is about 2.2 billion years old.

"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."