Answer:
6 billion
Explanation:
The world's population reached its first billion in 1804. By the year 1960, there were approximately three billion of people on earth. By the year 1999, the population grew to 6 billion.
According to recent prognostics, by the year 2024, the world's population would reach eight billion people.
The world population is the total number of humans currently occupying the earth. The highest population growth rates happened between the years 1950-1970.
The center of political and economic life in medieval Europe is manors. Thus option C is correct.
<h3>What is the political and economic life in medieval Europe?</h3>
In the Middle Ages, feudalism dominated both political and economic life. Kings and queens, as well as other monarchs known as lords, were able to keep their rule and position of authority.
The manor served as the center of life during that time. The local lord was in charge of the manor. People gathered in his expansive home or castle to celebrate special occasions or to defend themselves in case they were attacked.
Therefore, option C is appropriate.
Learn more about the manor, here:
brainly.com/question/1413689
#SPJ1
Answer:
<em>B. Humane methods of animal experimentation</em>
Explanation:
The regulations and guidelines of United States Department of Agriculture , Animal Welfare Act, Public Health Service (PHS), the Guide, and The Association for Assessment and Accreditation of Laboratory Animal Care International, or AAALAC, as applicable, requires organizations or entities that use animals in science, teaching, training, research or testing to provide instruction and training on humane methods of experimentation and research.
