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frozen [14]
2 years ago
12

After researching the possible effects of music, Elaina proposes that if people listen to faster-paced music, their pulse rates

will increase more than if they listen to slower music. Her mother listens to classic rock at a high volume for 30 minutes, her younger brother listens to classical music quietly while he sleeps at night, and her grandmother listens to two hours of rap at a medium volume. Elaina records each person's pulse before and after listening to the music. What is missing from Elaina's scientific investigation?
Chemistry
1 answer:
SCORPION-xisa [38]2 years ago
7 0

Answer:

Elaina's scientific investigation is missing controlled variables.

Explanation:

A good scientific investigation should vary only the factor that is studied (the speed of the music. All other factors should be kept constant.

She hasn’t controlled for <em>volume</em>. The volume of the music may affect the rate at which the listener’s heart rate will increase. She should have measured each person’s pulse after the same period of listening.

She hasn’t controlled for <em>age</em>. A grandmother may respond to loud music differently from a teenager. All her subjects should be about the same age.

She hasn’t controlled for <em>wakefulness</em>. A person may respond to music differently when awake than when asleep.

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Answer:

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2 years ago
How many miles of Fe2+ ions and MnO4- ions were titrated in each part 1 trial
Fudgin [204]

Answer:

In 1000 ml there is 0.10 moles of Fe 2+

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Hope this helps

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Victoria has a crate of vegetables that weighs 100 newtons. She exerts a force of 100 newtons to lift the crate with a pulley. W
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