Answer:
A: Cumulative recorder
Explanation:
B. F. Skinner was a psychologist, author, behaviorist and inventor of Operant conditioning chamber and Cumulative recorder. The purpose of cumulative recorder was to study the rate of operant conditioning. It is a process in which behavior of an organism is modified or an organism is conditioned to perform a specific behavior through giving punishment or reward.
For example: We teach a kid that he should not touch a hot stove because it will burn his hands, or we give him a box of candies to perform a specific task or behave in a certain way. Skinner used Cumulative recorder to find the effect of certain factors on behavior or response of an organism For example: the rate at which lever was pressed by a monkey to get bananas etc.
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erythrocytes- a red blood cell that (in humans) is typically a biconcave disc without a nucleus. Erythrocytes contain the pigment hemoglobin, which imparts the red color to blood, and transport oxygen and carbon dioxide to and from the tissues.
leukocytes- a colorless cell that circulates in the blood and body fluids and is involved in counteracting foreign substances and disease; a white (blood) cell. There are several types, all amoeboid cells with a nucleus, including lymphocytes, granulocytes, monocytes, and macrophages.
Try polypeptide, which is D.
By burning chemicals, also coal has been pollution since way back but since its used for electricity theyuse it anyways