If a substance has a half-life of 10 million years, what fraction of the atomsremain after 20 million years?

Answers

Answer 1

Answer: answer is 1/4 of the atoms

at 0 years it would be the full amount (X)

at 10 million years you have half: X/2

at 20 million years you have 1/4 because: (X/2)/2 will equal 1/4

Answer 2

Answer:

Answer: 1/4

Explanation:

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Why would increased levels of greenhouse gases contribute to higher temperatures on Earth?

Answers

Greenhouse gases are the gases in the atmosphere that keep the air in the atmosphere. It traps the sun's sunlight. Since the heat is trapped in here, it would contribute to higher temperatures.

I’m kinda of confuse ned help

What is the Guru Granth Sahib.

Answers

Answer:

The Guru Granth Sahib is the sacred text of Sikhism

Explanation:

Guru Granth Sahib, is the central religious text of Sikhism, considered by Sikhs to be the final sovereign Guru of the religion. It contains 1430 Angs, containing 5,894 hymns of 36 saint mystics which includes Sikh guru sahiban, Bhagats, Bhatts and gursikhs.

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This geographic feature is the primary reason for a budding economy on cook island.A. Beautiful beaches and pleasant climates
B. Beautiful volcanoes
C. Tropical plants.
D. Unique population of fish

Answers

A) beautiful beaches and pleasant climates

What activates a convection current, starting the flow of a fluid?A.
cold temperatures at the north pole

B.
heated liquids at the earth’s surface

C.
iron-rich rocks in the mantle

D.
temperature differences in the mantle

THIS IS FOR SCIENCE

Answers

The thing that activates a convection current, starting the flow of a fluid is D) temperature differences in the mantle.

Answer:

the answer is "D temperatures different in the mantle"

Explanation:

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Which of the following natural resources helps India fuel its nuclear power plants?

Answers

uranium because it is a fuel that is assembled in such a way that a controlled fission chain reaction can be used. The heat created by splitting the U-235 atoms is then used to make steam which spins a turbine to drive a generator, producing electricity.

Uranium is the correct answer.

Which of the following countries of South Asia has the highest poverty rate?Select one:
a. Bhutan
b. Bangladesh
c. Sri Lanka
d. Maldives

Answers

option b

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