"The pattern of electrons in their atoms" is the one among the following choices given in the question that <span>causes nickel and certain other metals to be magnetic. The correct option among all the options that are given in the question is the second option or option "B". I hope that the answer has helped you.</span>
Answer:
The time take is 
Explanation:
From the question we are told that
The decay constant is 
The percentage fall is 
The equation for radioactive decay is mathematically represented as
Where is 
is the new amount of the new the isotope while 
is the original
At initial 
% = 1
At 
% = 0.80
=> 
=>
Explanation:
At first sight, it doesn’t make sense that both fission and fusion release energy.
The key is in how tightly the nucleons are held together in a nucleus. If a nuclear reaction produces nuclei that are more tightly bound than the originals, then the excess energy will be released.
It turns out that the most tightly bound atomic nuclei are around the size of iron-56.
Thus, if you split a nucleus that is much larger than iron into smaller fragments, you will release energy because the smaller fragments are at a lower energy than the original nucleus.
If instead you fuse very light nuclei to get bigger products, energy is again released because the nucleons in the products are more tightly bound than in the original nuclei.
https://socratic.org/questions/how-are-fusion-and-fission-similar
