It protects us from harmful UV rays from the sun.
ANSWER: line b
I hope this answer is right
Answer:
The Red Sea and the Persian Gulf are parts of the Indian Ocean
Explanation:
A map for reference:
Answer:
The time will be "2 hours".
Explanation:
Around 10 km/hr, lava eruptions were travelling. The vents was just 15 km (9.3 mi) away Kalapana city as well as 20 km (12.6 mi) from Pahoa city.
So, we therefore need add the method, which would be: to taking out another time that civil defense officials just had to assess a city.
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Thus, to measure the time spent throughout the community of Kalapana,
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The civil defense officers provide 1.5 hours of time each assess the city of Kalapana.
In order to measure the time spent in the towns of Pahoa,
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A radioactive element with a half-life of 1,000 years, and starting mass of 20 grams, will need 2,000 years to decrease to 5 grams.
Explanation:
The radioactive elements all have a specific half-life. Each element's half-life is well known, and they are used by scientists of numerous fields as they are excellent for determining the age of a particular item, be it or organic or non-organic nature. In this case, we have a radioactive element with a half-life of 1,000 years, and starting mass of 20 grams.
The half-life basically means that half of the mass of an element is lost during a particular period of time. For the element in question we need to find out how much time will be needed for it to decrease to 5 grams. In order to get to the result, we just need to add 1,000 years on every decrease of half of the mass:
20/2 = 10
10/2 = 5
So in 1,000 years, the element in question will decrease to 10 grams, and in further 1,000 years (2,000 cumulatively) it will decrease to 5 grams.
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