What's the leading cause of air pollution?

Can someone me with this and tell me what’s fracking and what does it have to do with carbon, carbon dioxide, or fossil fuels?

Briefly describe the scenario that was discussed in the behaving brain that demonstrated that the brain can change based on state or mood. which disease could the research involving rats and learning experiments that was discussed in the behaving brain ultimately with? in the behaving brain, what is a common misunderstanding about amnesia that was mentioned? what is the truth about amnesia that's mentioned? what does research discussed in the responsive brain show to be different in men and women's reaction to touch? what was discussed in the responsive brain as being brain-based and a vital part of normal growth and development in young children? in the responsive brain, what do they discuss as a possibility for leading to deficiencies in cognitive impairment as we age? in the responsive brain, what did the research involving african cichlid fish demonstrate? briefly describe the back story and affliction of the author of peter pan. what did you find most interesting about the behaving brain video, and why? what did you find most interesting about the responsive brain video, and w

How do cells grow and reproduce to maintain homeostasis?