what is A substance that is formed as the result of a chemical reaction and A starting material in a chemical reaction. any help will be appreciated

Enzyme speed up chemical reaction are which type of marcomolecule? a. carbohhydrates b. protiens c. lipids d. nucleic acids

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.

Pulmonary arteries carry highly oxygenated blood. true or false?