I believe the answer is 20 feet. According to McBurney and Collings, the average threshold of human hearing is the tick of a watch from 20 feet in very quiet condition.
The human hearing range is a description of the pitches and loudness levels a person can hear before feeling discomfort. There is a variety of sounds in our environment, ranging from faint sounds like birdsong and rustling leaves to louder sounds like music, yelling, and industrial noise.
<span>Enzymes are called biocatalysts because they function in chemical reactions that involve living organisms [biologial organisms]. Enzymes generally increase the rate of metabolic reactions by lowering the activation energy, making it easier for the reaction to occur easily and rapidly. Without enzymes, some metabolic reactions may take a very long time before they are completed. Enzymes used in laboratory chemical reactions are not biocatalysts because they are not catalysing reactions in biological organisms. </span>
Karen is NOT correct. This is because the sun's energy is a renewable resource. This means that its use is sustainable hence it is a substance of economic value that can be replaced or replenished in the same or less amount of time as it takes to draw the supply down. Though the sun is a finite resource, it cannot be depleted within human timescale.
Prosimians are a group of less-developed primates.
<h3>What are Prosimians?</h3>
They are a group of primates with some less-developed features as compared to other primates.
The more developed primates are referred to as Simians and these include humans, apes, and monkeys.
Prosimians include both living and extinct animals such as the lemur, lorises, and galagos.
More on Prosimians can be found here: brainly.com/question/14521463
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