Answer:
Explanation:
Half life of Nobelium-253 is 97 seconds . That means after every 97 seconds half of the Nobelium amount will be disintegrated .
Time taken in bringing the sample to laboratory = 291 seconds
291 second = 291 / 97 half life
n = 3
N = 
N₀ is original mass , N is mass after n number of half life.
N = 5 mg x 
= .625 mg
Only 0.625 mg of Nobelium-253 will be left .
The Permian-Triassic extinction event<span> about 250 million years ago was the deadliest: More than 90 percent of all species perished. Many scientists believe an asteroid or comet triggered the massive die-off, but, again, no crater has been found. Another strong contender is flood volcanism from the Siberian Traps, a large igneous province in Russia. Impact-triggered volcanism is yet another possibility.</span>
Answer:
C
Explanation:
Photosynthesis is usually represented by the equation Carbon dioxide + water + light --> glucose + oxygen.
Therefore, <u>A substance is water</u> and <u>B is glucose</u>
A is incorrect because it's talking about glucose
B is incorrect because it's talking about chlorophyll, the important pigment in photosynthesis
D is incorrect because it combines to form oxygen, not hydrogen
"<span>A. The polar regions have long winters and short, cool summers." would be the correct answer.
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