D. Cambodia (mostly), Thailand, Vietnam
well <span>It's because sunlight hits the equator more directly throughout the whole year. Sun equals life. so therefore the equator have more vegetation and and warmer climate and thus it has more life than Canada which is at higher latitudes where it is cold most for a large part of the year.</span>
Urban
I don’t know what else to but but that’s the answer lol
I really would think something besides the question
More than 75 percent
Explanation:
Let us carefully analyze this problem:
The half life of the rubidium isotope = 50 billion years
The half-life of a radioactive isotope is the time it takes for it to decay to half of its original amount.
Every 50years, we know that a rubidium isotope would split into half.
Initially when the isotope was formed, we would only have the parent atoms there. There wont be any daughter;
ratio of parent to daughter = 100 : 0
When the isotope decays to half; we would have equal number of parent and daughter:
ratio of parent to daughter at half life = 50 : 50
The age of the earth is about 4.6billion years;
this is;
x 100 = 9.2% of the half-life of the rubidium isotope.
At this time, we should know that only 9.2 percent of the daughter would have been formed.
The remaining parent would be 100 - 9.2 = 90.8% would still be left undecayed.
The ratio of parent to daughter = 90.8 : 9.2
This is more than 75% of the parent
learn more
Radioactive decay brainly.com/question/10125168
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