Answer: (A) Surveys are generally cheaper to conduct.
Explanation:
Both surveys and experiments are valid means to scientifically establish data about groups of people and how the way specific variables influence them. A survey examines the way a variable we have no control over has affected, for example, a group of people. In an experiment, one of the variables is manipulated while the other one is measured.
Surveys are comparatively inexpensive, especially if they are online surveys, and even if incentives are provided to participants.
I believe the answer is: physical development
In longitudinal study same subjects over a certain period of time. From the study above, we can see that on-field-performance is the dependent variables. Since there is no way for the researchers to conduct and proof the psychological development, physical development ia the most suitable choice.
A. they are a source of calcium
Investment capital to reinvigorate agricultural production. Investment capital for increased industrial production,which would create new jobs for the freed slaves.
Answer:
conquer other nations and reduced people to slavery
