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NARA [144]
3 years ago
13

30 POINTS!!!!!!

Biology
2 answers:
vladimir1956 [14]3 years ago
8 0
I believe the answer is B.
satela [25.4K]3 years ago
3 0
B. The valves of the aorta and pulmonary artery close, producing the first heartbeat. Is the correct answer. Hope this helped. Have a good day! :)
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In the exercise-depression study by Blumenthal et al. (the SMILE study), which of the treatments had the best success when consi
vodka [1.7K]

Answer:

In the exercise-depression study by Blumenthal et al. (the SMILE study), which of the treatments had the best success when considering the percentage of individuals who had either recovered or at least partially recovered at a 6-month follow-up period? B. Exercise group.

Explanation:

Exercise has different depression-reducing effects. It enables the body to producte endorphins that reduce sensations of pain. Moreover, it changes the  neurotransmitter levels associated with depression (for example, norepinephrine) and it developes a sense of mastery and self-control through regular practice. <em>The SMILE study concludes that aerobic exercise on MDD remission extend the benefits</em> and it might be better than the benefits of antidepressant use.

5 0
3 years ago
The new Hazard Communication Standards provide teachers and students the right to __________ chemical hazards.
Aleonysh [2.5K]

The new Hazard Communication Standards provide teachers and students the right to manipulate chemical hazards.

Chemical hazards are non-biological substances that can cause damage to health. These are used in different enterprises, companies, school, universities and laboratories for different purposes such as cleaning, disinfection, scientific experiments, among others. When handling them, <u>employees are exposed to them and are vulnerable to harm from these chemicals</u>.  

There are many types of hazardous chemicals to be wary of, such as:

  • Carcinogens
  • Neurotoxins
  • Acids
  • Systemic toxins
  • Asmogens
  • Silica dust
  • Lead

In the workplace, exposure to these substances represents a real occupational hazard and there must be regulations to ensure that they are safe to handle.

The Occupational Safety and Health Administration (OSHA) is the agency of the U.S. Department of Labor which determined the Hazard Communication Standards. <u>This is a document with the necessary information to study the hazards of the chemical substances used by different employees in the companies</u>, so that they are aware of the dangers of these substances. These employees have the right to know exactly what compounds they handle and the risks involved in their use as well as the precautions and care to be taken.

Therefore, by having these safety standards in place in schools and universities, teachers and students have the possibility and the right to handle chemical hazards safely to be able to conduct the class normally and learn what is necessary.

Learn more about chemical hazards here: brainly.com/question/13113515

6 0
3 years ago
¿Qué características crees que deben tener los métodos anticonceptivos para ser eficaces en el control de la natalidad?
Tanzania [10]

Answer:

Los métodos anticonceptivos para ser eficaces en el control de la natalidad deben ser seguros para las personas que los utilizan, es decir, no tener efectos adversos, o al menos, la menor cantidad posible. Ser reversibles, es decir, que no generen infertilidad de por vida. Deben ser además fáciles de usar, cómodos y fáciles de conseguir, esto es, económicos. Además deben ser eficientes en su objetivo de evitar la concepción, que es para lo que fueron creados.

Explanation:

La tasa de eficacia de un método anticonceptivo se mide por la cantidad de embarazos que se producen cada 100. Esta parece ser la característica más importante, y si bien es una de las más importantes, hay que tener en cuenta todos los otros factores mencionados, es decir que la gente pueda acceder a ellos, sean cómodos, seguros y a un precio coherente.

5 0
3 years ago
What are abiotic and biotic factors?
Setler79 [48]

Answer:

abiotic factors are factors that are not organ or biotic as one would say like the nevirmwnt or air or water biotic factors are things like tress food plants ect

3 0
3 years ago
Read 2 more answers
Imagine a foreign mountain lion species is introduced into the ecosystem. How will it affect the other organisms?
zysi [14]

It will probably take the highest roll in the food chain which then factors to the other animals either dying, or competing for resources. making the ecosystem unstable.

7 0
3 years ago
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