Answer:
   the very long river
Explanation:
Larger rocks tend to settle out of the water flow sooner than smaller rocks do, so the rocks remaining at the end of a very long river would tend to be very small. A very short river may still be carrying somewhat larger rocks.
The very long river probably drops the smallest rock pieces near the ocean.
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Perhaps the implied assumption here is that a very short river will have a higher gradient than a very long river. Another assumption is that rocks are picked up nearer the headwaters, and the gradient decreases with distance.
If both rivers end at a waterfall into the ocean, they may very well carry the same sort of rock size distribution. If the short river traverses muddy terrain, and the longer river traverses rocky terrain, the answer may be reversed.
 
        
             
        
        
        
Answer:
Hypothalamus 
Explanation:
The Hypothalamus is located below the cerebral cortex. It's involved with basic functions like eating, sex, temperature control, sleep, aggression. It's main function is to produce sex, growth and stress related hormones carried down axons to the pituitary gland. When carried out, it's then released into the bloodstream to activate and organize distant body systems.
 
        
             
        
        
        
Subjects in the population are sampled by a random process, using either a random number generator or a random number table, so that each person remaining in the population has the same probability of being selected for the sample.
How to Estimate a Population Total from a Simple Random Sample
1. This lesson describes how to estimate a population total, given survey data from a simple random sample. ...
2. Sample mean = x = Σx / n.
3. Population total = t = Nx.
4. where N is the number of observations in the population, and x is the sample mean.
A simple random sample is a subset of a statistical population in which each member of the subset has an equal probability of being chosen. ... In this case, the population is all 250 employees, and the sample is random because each employee has an equal chance of being chosen.
Random sampling is a part of the sampling technique in which each sample has an equal probability of being chosen. A sample chosen randomly is meant to be an unbiased representation of the total population.