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Murljashka [212]
3 years ago
10

The force of contraction (of the heart) can be changed by:

Social Studies
1 answer:
Dmitry [639]3 years ago
8 0

The correct answer is letter A

Sinoatrial node (SA) or pacemaker or sino-atrial node: special region of the heart, which controls the heart rate. It is located near the junction between the right atrium and the superior vena cava and consists of a cluster of specialized muscle cells. The rhythmic frequency of these muscle fibers is approximately 72 contractions per minute, while the atrial muscle contracts about 60 times per minute and the ventricular muscle, about 20 times per minute. Due to the fact that the sinoatrial node has a faster rhythmic frequency in relation to the other parts of the heart, the impulses originating from it spread to the atria and ventricles, stimulating these areas so quickly, so that the rhythm of the SA node becomes the rhythm of the whole heart; that's why it's called a pacemaker.

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When an ad for Everlast fitness equipment encourages bike riders to train harder and states Everlast's power packs enable them t
Masteriza [31]

Answer:it is focused on the individual rider's quest for Achievement

Explanation:

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Someone who has to train harder and make sure they find means to recover fast are mostly driven by a goal to achieve something , they don't want to waste time they keep consistant pace and don't allow interruptions such a person needs a boost like energy power drink that will assist them to keep going until they achieve their goal ;hence we can safely say this ad is focused on an individual rider's quest for achievement

7 0
3 years ago
What is 2+2-5+88-1253+8+22-778
VMariaS [17]
The answer is -1914. Please make my answer brainliest
5 0
3 years ago
Straighterline the lowest or most basic needs in maslow's classification system are called _______ needs.
Keith_Richards [23]

Straighterline the lowest or most basic needs in maslow's classification system are called <u>"biological"</u> needs.


Maslow's hierarchy of needs is a motivational theory in psychology containing a five-level model of human needs, frequently delineated as progressive levels inside a pyramid.  

"Biological/Physiological" needs are the physical prerequisites for human survival. In the event that these necessities are not met, the human body can't work and will eventually fall flat. Physiological necessities are believed to be the most imperative and they are needs that ought to be met first.

4 0
3 years ago
how do th location and climate of the United kingdom and russia affect how each country conducts trade
AnnZ [28]
United Kingdom is surrounded with bodies of water; thus, it is easier for them to trade with people from different countries all over the world. Ships carrying various goods from different parts of the world would dock in UK ports and trade their goods for the goods found in UK. People living in UK has livelihoods that are depended on land (farming) and water (fishing).

Since UK is surrounded by bodies of water, it enjoys a milder climate compared with Russia.

Russia, on the otherhand, occupies some parts of Europe and Asia. But, Russians can not maximize the use of their land area since there are parts of Russia wherein there are permanently frozen land. Russia is also bordered by 15 countries with no access to waterways, making trading difficult but possible.

Most Russians live in the European part of the country because it has a better weather condition and trade among neighbouring countries can easily be done.
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3 years ago
A(n) ____, also called an expert system, attempts to mimic the human ability to engage pertinent facts and string them together
frosja888 [35]

Answer:

rule-based system is the correct answer.

Explanation:

8 0
3 years ago
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