Within the cardiovascular system what is compered to the branches of a tree?

Which organelles are involved in energy conversion

How is the carbon cycle related to global warming ?

Many organizations release indexes used to measure the development of the world's countries. as we learned in this lesson, these indexes measure many factors, from life expectancy to happiness. in your opinion, what are the three most important factors we can use to determine how developed a country might be? explain your answers in a few sentences.