Answer:
B only
Explanation:
Using the VSEPR principle, the electron bond pairs and the lone pairs on the middle atom help us predict the structure of the molecule. The shape of a molecule is determined by the position of the nucleus and its electrons. The electrons and the nucleus settle in positions that minimize repulsion and maximize attraction.
Answer: It depends on the element.
Explanation: Every element has a different amount of protons in its nucleus. It is the same as its atomic number on the periodic table. For example: Hydrogen has an atomic number of 1 because it has 1 proton in its nucleus, Helium has 2, Carbon has 6, Platnium has 78, and so on...
Answer: Seastars prey on mussels and shellfish which would otherwise have no other natural predators. Herbivorous fish like the butterflyfish pictured to the left prey on marine algae. Without this crucial predator-prey balance, the algae would over-grow, which would then kill coral, as they compete for the same resources.