Pretty much Saudi Arabia, Iran, Iraq, Syria.
Answer:
Gran papel.
Explicación:
La historia ha hecho grandes contribuciones al desarrollo de la cartografía. El descubrimiento de nuevas tierras a través del viaje de personas en el mar permite al mundo trazar un mapa de la tierra. Estos mapeos dan información a diferentes países y se produce la transferencia de cultura, humanos y otros materiales. Este mapeo también permite a las personas comerciar en lugares lejanos. De esta manera se inició el comercio entre diferentes países. Entonces podemos decir que la historia juega un gran papel en el desarrollo de la cartografía.
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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Answer:
it is 20% which is correct answer