Vertebrates developed about 550 million years ago. The oldest vertebrate fossils are those of FISH with no jaws. These e<span>arly jawless fish did not have paired fins and their bodies were covered with heavy, bony scaled, but their skeletons were made of cartilage. For the next 50 million years, they were the only vertebrates.</span>
For questions 11-15
11. Magnesium Oxide is a combination between Magnesium and oxygen so the formula will be MgO
12. Calcium Chloride is a combination between Calcium and Chlorine, so the formula will be CaCl₂ the ₂ comes from the fact that there is two Chlorine atoms
13. Lithium Sulfide is a combination between Two lithium and a sulfur atoms,
so the formula will be Li₂S The ₂ coming from the two lithium atoms
14. Barium Selenide is a combination between Barium and Selenium so the formula will be BaSe
15. Aluminum Oxide is a combination between Aluminum and Oxygen, there are two Aluminum atoms and three Oxygen atoms, so it will make Al₂O₃
Hope this helps
The statement that provides the best explanation for the
increased growth of the in the pond is ‘The fish grew to be approximately 6
centimeters long in the first year, and after that, growth in length stopped.’
The answer would be Energy.