4. compared to earth's crust, earth's core is believed to be
a. less dense, cooler, and composed of more iron.
b. less dense, hotter, and composed of less iron.
c. denser, hotter, and composed of more iron.
d. denser, cooler, composed of less iron.

If you could drill a hole straight to the center of the earth, and keep track of what the hole is going through, youwould find: a) you would go through one sort of material, and then a different, denser material, and then a still-different, still-denser material, because the planet is made of concentric layers, sort of like an onion.b) you would go through one sort of material all the way to the center, because the planet is all mixed up.c) if your hole started at the north pole, you would go through different layers of different materials, but ifyour hole started at the equator, you would go through one sort of material all the way to the center.d) if your hole started at the equator, you would go through different layers of different materials, but if yourhole started at the north pole, you would go through one sort of material all the way to the center.e) you would strike diet pepsi when you got to the center.

70 pts answer the following questions in full sentences and paragraphs, using at least 150 words, in the essay box below. 1. which organisms are carnivores? herbivores? omnivores? 2. if the ecosystem is balanced, which populations should be the largest? the smallest? 3. imagine a group of hunters kills half of the rabbit population. how will the other organisms be affected? 4. imagine disease kills 85 percent of the wolf population. how will the other organisms be affected? 5. imagine a foreign mountain lion species is introduced into the ecosystem. how will the other organisms be affected?

At which boundary does subduction stop occurring, resulting in a mountain range?