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Murljashka [212]
4 years ago
10

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

Social Studies
1 answer:
Dmitry [639]4 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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During the 1930s, a rivalry between Max Schmeling and which African-American athlete enhanced anti-German sentiment in the black
dem82 [27]

Answer:

During the 1930s, a rivalry between Max Schmeling and Joe Louis enhanced anti-German sentiment in the black community.

Explanation:

It was June, 1936, until then undefeated Joe Louis received the German Max Schmeling at the Yankee Stadium in New York. "The Detroit bomber," as they said to Louis, had become an idol of the crowds, especially in the young men and women of color who saw in him a hope to end the racism existing at that time in the United States.

The German, the only boxing world champion in his country, came on behalf of a dictatorial regime that was at its boiling point. Adolf Hitler had begun with his expansionist policy and his sinister plan was already underway. That is why the Kaiser and all his propaganda apparatus could not miss the opportunity. In addition to organizing the Olympic Games in Berlin in the same year, this fight was an excellent opportunity to demonstrate the superiority of the "White race".

In the 12th round, Schmeling knocked out Louis leaving the entire stadium muted, it was the first time Louis lost, in full political conflict and over against a German. With or without his consent, Max's victory was used as the political propaganda of Nazism through its representation as "a triumph of the White race over blacks" and the boxer was elevated to the status of national hero.

The following year, while Hitler signed the agreement that would formalize the group of "the powers of the axis", Louis obtained the title of world champion after winning by nock out in the 8th assault on James Braddock, becoming the first black to be champion of the world since Jack Johnson had been in 1915. Joe said he would not feel a true champion, until he defeated the only boxer who had made him know the canvas. And after two minor fights, he signed the contract to carry out "the great revenge."

The date was agreed on June 22, 1938. In the days before the fight, Joseph (his original name) visited the then President Franklin Delano Roosevelt. According to the New York Times, the president's textual words for the boxer were “Joe, we need muscles like yours to defeat Germany. Remember that when a cause is fair, an American never loses”, carrying even more political connotations to combat. The Americans were desperate, thirsty for revenge. For them, revenge was nothing more than the good against the bad of the film, the free United States against Nazi Germany, freedom against fascism. It was the fight of good against evil.

Incredibly, the fight lasted only 124 seconds. It was two minutes and a little more in which Louis devoured the German. When the bell rang Joe shot out of his corner and put his rival against the ropes. After a great combination, Max, about to fall, was supported by the ropes. The rain of blows of Louis did not stop, Schmeling only raised his fists showing a warm defense. He fell to the ground for the first time and got up. Already reincorporated, he pounced on the American, who waited for him with a right hand that deposited him directly on the canvas. When the German tried to recover, the white towel that marked the end fell from his corner.

Good had triumphed over evil and a person of color was the cover of the world's leading sports newspapers. Finally, Joe Louis had been able to get even with who had been the only one who had made him know the dust of defeat. And how! Only two minutes and four seconds were enough for Schmeling to finally fall into a fight in which he could only throw two strokes.

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