Why do geologists think Earth's core contains mostly iron?
A. The entire core is a solid mass.
B. The crust also contains mostly iron.
C. Comets contain more iron than Earth's crust does.
D. Iron is the lightest element.

If the experiment was perfomed more then once and you get the same results

The return of the wolf to yellowstone national park will probably affect the bird population to some degree, not significantly. while wolves will hunt birds when necessary, they prefer to hunt larger prey. the bird population will most likely only be affected when hunting is scarce for the wolves. birds of prey will also probably not be affected as much as other birds who spend more time on the ground hunting for food as the tend to spend more time in the air or in trees since they do not need to stay on the ground for long due to the nature of the way they hunt.

Im not sure if you still need this but the answer is 300 hz450 hz  i just did this lesson so , wish you the best of luck and take care