Answer
the atmosphere is the important part of what makes earth livable and it blocks the sun's dangerous ray from reaching the earth.
Answer:
A duck walked up to a lemonade stand and he said t the man running the stand, "Hey! BUM BUM BUM Got any grapes?"
Explanation:
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
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Radioactive decay brainly.com/question/10125168
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Among the choices provided above the answer would be 30%. The 30% of the <span>population practices subsistence farming. Thank you for posting you Geography question here at brainly. I hope the answer will help you. </span>