12. The answer would be C. 1.50 s. This is because if you divide 60 by 40, you will get 1.5.
13. For this one I'm not sure, but what I can tell you is that the heavier something is the faster it will sink, the lighter it is, it will float.
Answer:
4
Explanation:
The weight of the rock is W = mg = (80 kg) (10 m/s²) = 800 N.
The mechanical advantage is therefore 800 N / 200 N = 4.
Eight electrons surrounding each non-hydrogen atom is the optimal electronic arrangement for covalent molecules because it is needed to achieve an octet structure and is necessary to fill both the s and p subshells of electrons.
<h3>What is Covalent bonding?</h3>
This is the type of bonding which involves the sharing of electrons between atoms of an element.
This is done to achieve an octet configuration thereby making them stable and less reactive thereby making it the most appropriate choice.
Read more about Covalent bonding here brainly.com/question/3447218
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I would say yes, a magnetic reversal a threat to life on Earth. Base on articles, it is the end of the world if that happens. <span>Some people believe global cataclysm will occur when Earth's magnetic poles reverse. When north goes south, they say, the continents will lurch in one direction or the other, triggering massive earthquakes, rapid climate change and species extinctions.</span>