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Advocard [28]
3 years ago
7

When the first antibiotics became available in the late 1940s and early 1950s, these antibiotics were effective against all bact

erial infections. Today however, there are a multitude of antibiotic resistant bacterial infections. What conclusion can be drawn? A) Antibiotics of today are not as strong as those in the past. B) Antibiotics cause DNA mutations in bacteria, and over time, this has led to resistance. C) Over time, bacteria have turned into viruses, and antibiotics have no affect over viruses. D) Bacteria have become resistant to antibiotics over time due to evolution by means of natural selection.
Biology
2 answers:
kirza4 [7]3 years ago
8 0
The correct answer would be D.

After many generations, only those with genes suitable to live in harsh environments can live. These genes are passed onto their offspring and then we see a rise in antibiotic resistant strains of bacteria such as Methicillin Resistant Staphylococcus Aureus (MRSA).
Dmitry [639]3 years ago
6 0
Answer is D. how do i no? i got it right on USA test prep. 
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Explain why extended exercise is considered to be "healthy"
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3 0
3 years ago
Human impact on our ecology review
belka [17]

Answer:

Humans have impacted nature in a lot of ways. I also think that society has shifted humanity away from what matters most in life, we've changed as a species and I want to keep it as real as possible. but uh... what was your question?

Explanation:

May I have brainliest please? :)

3 0
2 years ago
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A roofer needs to get a stack of shingles onto a roof. Pulling the shingles up manually uses 1,549 n of force. The roofer decide
AURORKA [14]

Answer:

3.47

Explanation:

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F_o = Output force = 1549\ \text{N}

F_i = Input force = 446\ \text{N}

So,

MA=\dfrac{F_o}{F_i}\\\Rightarrow MA=\dfrac{1549}{446}\\\Rightarrow MA=3.47

The mechanical advantage of the pulley's is 3.47.

5 0
2 years ago
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3 0
3 years ago
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