Answer:
5 mg
Explanation:
If one half life is 4 hours, then 3 half lives is 12 hours.
This means that the sample will decay to 1/8 of its original amount.
So, the answer is 40(1/8) = 5 mg.
Answer:
82.4 s
Explanation:
Find the NUMBEr of half lives...then multiply by 54.3
2.27 = 6.5 (1/2)^n
log (2.27/6.5) / log (1/2) = n = 1.52 half lives
1.52 * 54.3 = 82.4 s
In my opinion yes, as of now, almost anyone could get there hands on lets say an explosive. Have you heard of dynamite fishing? It is illegal, but it is still done once people have access to dynamite, then what ends up happening not only do marine wildlife get killed but it pollutes the water and lessens the chance of the natural cycle of life. Also there are several other factors, firstly, what will you do with an explosive once you get your hands on it? Perhaps you could just use an explosive for fun/personal entertainment...that isn't right and it could harm people. So, to conclude the harder it is for people to access explosives or even acclerants the better...and to add this can be possible by making people get like some sort of licence to use them, and let them be trained in certain conditions so that there is no regrets once they have access to them. I know my idea sounds far fetched but its a thought!
At almost the opposite point on the Earth's surface, the "P" waves reappear. The shadow zone exists because the waves are refracted as they pass through the boundary between the mantle and the core and are diverted from their original paths.
