Answer:
Rivers transport particles, from fine ones such as silt in turbid water to coarser ones such as sand, gravel, and boulders associated with bed-load transport. The speed and turbulence of currents enable transportation of these materials. When riverbed gradient or the river flow diminishes, particles tend to drop out.
Explanation:
Answer:
The amount of fuel used to heat and cool your home can be reduced by good insulation.
Answer:
A and C
Explanation:
The rock layers must have formed at different times because they contain two different biozones. The rock layer containing the trilobites must have formed before the one containing the ammonites. The key thing to note here is that the Trilobites only lived from 540 to 248 million years ago. And that the Ammonites were from 245 to 65 million years ago. So there's a 3 million year gap between these 2 different creatures where neither of them existed. So the dig where the trilobites were found has to be at least 3 million years older than the dig where the Ammonites were found. So with that in mind, let's look at the options and see what makes sense.
The rock layers must have formed at the same time because they both contain biozones. * This is nonsense no matter what dates you're speaking of. In effect it claims that all rocks that indicate life were created at the same time. So this is definitely a bad choice.
The rock layers must have formed at different times because they contain two different biozones. * This is technically incorrect since it assumes that all biozones represent an unique period of time which is incorrect. However, since the biozones represented by the presence of Trilobites and Ammonites don't overlap, it is true that these these rock layers were formed at different times. I would have preferred if this option said "non overlapping biozones". But on the balance, I'd consider this option to be true, so it should be selected.
The rock layer containing the trilobites must have formed before the one containing the ammonites. * This is definitely true since the last Trilobite died about 3 million years before the first Ammonite lived. So this is a correct choice.
The rock layer containing the trilobites must have formed after the one containing the ammonites.
* This is the opposite of the previous option. And since the previous option was true, this option must be false. So this is a bad choice
Answer:
D.
Explanation:
The many people swarming to Africa, could'nt have reduced diversity...It would have increased it. Elimination of communism? Nope...The head of the country wouldnt be influenced too much by the people coming in. European influence would'nt have been reduced all too much either. The only answer id D. It brought new ideas to the continent. The people coming to Africa would have had a whole din of ideas, just waiting to improve the average African life. So, yeah, they did improve it.
