Answer: Principle of motion economy.
Explanation: principle of motion economy developed by Frank and Lillian Gilbreth are guidelines to help determine the work method, workplace layout, tools, and equipment.
The aim of this is to help in identifying and replicating one best way to complete a task and also minimize the physical and perceptual loads imposed on people engaged in that task.
D because it seams most logical
Explanation and answer:
A rain shadow is a patch of land that has been forced to become a desert because mountain ranges blocked all plant-growing, rainy weather. On one side of the mountain, wet weather systems drop rain and snow. On the other side of the mountain—the rain shadow side—all that precipitation is blocked.
In a rain shadow, it’s warm and dry. On the other side of the mountain, it’s wet and cool. Why is there a difference? When an air mass moves from a low elevation to a high elevation, it expands and cools. This cool air cannot hold moisture as well as warm air. Cool air forms clouds, which drop rain and snow, as it rises up a mountain. After the air mass crosses over the peak of the mountain and starts down the other side, the air warms up and the clouds dissipate. That means there is less rainfall.
You’ll often find rain shadows next to some of the world’s most famous mountain ranges. Death Valley, a desert in the U.S. states of California and Nevada, is so hot and dry because it is in the rain shadow of the Sierra Nevada mountain range. The Tibetan Plateau, a rain shadow in Tibet, China, and India has the enormous Himalaya mountain range to thank for its dry climate.
Answer:
The answer is non-participant observation method.
Explanation:
In this method, the researcher is not part of the group being studied. The reseracher must decide beforehand if the study is realistic, ethical and relevant for the research. Among the many different ways to carry out this method, it is posible for the researcher to observe a group at different times and locations, for short periods.
It is also important for the researcher to record not only the behaviour observed, but also the type of behaviour that did NOT occur.
This is of course a very complex question that does not have a definitive answer, but 1850s would be a good decade to start counting as "Modern". This was a decade of the telegraph and Darwin's The Origin of Species.
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