The crest Is the highest point of the wave.
No, predators do not only kill the old and sick prey. They will go after any of the prey, including the strong ones and the children. The reason they often go after the old and sick prey is because they're easier to pick off, whether they are on their own or in a pack. Predators will go after any one of the members of their prey, but prefer the old and/or sick as it requires less energy.
Ans ; It would have to be closer for it to be in a circular orbit twice as fast. One moon cycle would be 2 weeks instead of 4 so our months would have been based on 2 week cycles making for 24 months. Tides would be less synchronous between days and much more intense because of how close it would be. This would have left a very different land map. Tidal forces would force the moon to rip apart sooner than with it's present orbit creating an important ring system around earth earlier.
The answer would be B) oxygen. In the electron transport chain, oxygen is a reactant. It reacts with 4 electrons and 4 hydrogens to form 2 water molecules. NAD plus is a product of NADH losing an electron. FAD is a product of FADH2 losing an electron.
