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3 years ago

Select all the correct answers.

Physics

2 answers:

Phantasy [73]3 years ago

8 0

Answer:

When water freezes, it's volume INcreases, which naturally results in a DEcrease in it's density. That's why cubes and bergs float.

Explanation:

I'm pretty sure that water is the only known substance that behaves this way. Which is lucky for us, because if it didn't, then life on Earth would be impossible. Oceans and lakes would freeze from the bottom up. Once! And then they would never thaw, because the sun could never cut through the layer of warm water on top, to melt the ice below.

Mamont248 [21]3 years ago

7 0

When water freezes, it's volume INcreases, which naturally results in a DEcrease in it's density. That's why cubes and bergs float.

I'm pretty sure that water is the only known substance that behaves this way. Which is lucky for us, because if it didn't, then life on Earth would be impossible. Oceans and lakes would freeze from the bottom up. Once! And then they would never thaw, because the sun could never cut through the layer of warm water on top, to melt the ice below.

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3 years ago

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Answer:

Failure rate = 20%

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Explanation:

given data

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one failed = 20 hours

another fail at = 140 hours

solution

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so here Total up time will be

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and here

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so it will be = (Total up time) ÷ (number of breakdowns) .......2

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and

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and

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