Let me know the answer and why

An example of internal feedback working to maintain homeostasis is your a. decreased respiration rate when you are studying b. decreased heart rate when you are sad c. increased respiration rate when your muscles need more oxygen d. increased heart rate when your lungs need more oxygen

In which state was more than 100 billion tons of coal mined in 2005?

If an organ has six haploid chromosomes,how many chromosomes are present. 6 12