Answer:
5 : 9
Step-by-step explanation:
Answer:
The answer is 2.5 hours. That's how long it would take the train to travel 270 kilometers.
mark me brainliest!
Answer:
2.5 * 10^-5
Step-by-step explanation:
2.5 * 10^-5
If the number is between 1 and -1 excluding 0. Then
count the number of zeros
add 1 more
write the notation of where you put the decimal place
The power is minus and equal to the number of zeros + 1
0.000025
zeros: the number of zeros = 4
Add 1: 4 + 1 = 5
Decimal goes between the 2 and the 5
2.5
Power: = - 5
Answer: 2.5 * 10^-5
<span>half-life means you divide by 2
21.6 / 3.6 = 6 hf (hf = half-life)
then you divide by 2^6
6.02 x 10^23 / 2^6 = 9.40625 x 10^21 atoms
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26
3hf ===> 2^3
10.0 / 2^3 = 1.25 gram (remaining)
answer : 10 - 1.25 = 8.75g
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27
128 / 2^n = 2
64 = 2^n
n = 6
24 /6 = 4
4 days is the half-live of the sample
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28
2.5/4.46 of 50% initial mass
(2.5/4.46) x 0.5 x 2 = 0.5605 g
answer: 2 - 0.5605 = 1.4395 g
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29
2^7 = 128
so 7 half-lifes
7* 8040 = 56200 days
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30
the time of 10 half-lifes
= 10 x 0.334s = 3.34s </span><span>
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