By not misusing the information regarding the feeling,needs and behavior of participants.The researcher can control harmful behavior.
<u>Explanation:</u>
Psychological research is undertaken to study human behavior. It helps us to measure and classify human behavior. Such research identifies what is normal behavior. If the behavior is abnormal than that can be known through this kind of research.
In Psychological research, it is of the utmost importance to respect the dignity of others. This will prevent any kind of harmful behavior. For example, the researchers must not manipulate the participants. If a researcher has information regarding the feelings and emotions of participants then they must not misuse it.
 
 
        
             
        
        
        
B. 
randomization is often hard to achieve.
 
        
             
        
        
        
Answer:
a) Malthus ignored other factors like technological change.
Explanation:
Thomas Malthus (1766-1834) was an English cleric and a scholar, most known for his demographics theory. He is an author of <em>An Essay on the Principle of Population</em>, where he observed that increasing production of food resulted in improved well-being of the population, but this was temporary because it led to a population growth. Larger population led to the restoration of original production per capita. 
He was mainly wrong because he did not account for improvement in technology of production. Development and widespread use of technology meant that it is not needed to use the same amount of energy to produce goods. Production increased much faster than the increase of population, which resulted in a failure of his theory.
 
        
             
        
        
        
The death of Vladimir Lenin and the rise of Joseph Stalin, I believe.
        
                    
             
        
        
        
The pricing model requires the consumer to initially pay to download the app and then offers the ability to buy additional functionality are <u>Paid apps with</u><u> in-app purchases </u>
This is further explained below.
<h3>What are <u>Paid apps with</u><u>
 in-app purchases</u>?</h3>
Generally, Inside of an app, you may pay for additional material or subscriptions via a process known as "in-app purchases." 
In-app purchases are not available in every app. Find the app in question inside the App Store before you buy it or download it to see whether or not it supports in-app purchases.
 Then seek for a phrase that says "In-App Purchases" close to the price of the app or the Get button.
In conclusion, The pricing model requires the customer to pay to download the app initially and then provides the option to acquire more functionality via in-app purchases. 
These applications are considered to be paid apps with in-app purchases.
 
Read more about <u>Paid apps with</u><u> in-app purchases </u>
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