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If we do nothing, the world will become significantly less habitable. ... Scientists have studied global warming for more than 100 years. ... The cumulative effect is to raise the planet's temperature. ... Scientists have taken detailed measurements of carbon dioxide (CO2) levels since the late 1950s
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ok there is the yemen civil war,syiran civil war ,iraqi insurgencys,kurdi insurgeny fight iran and many more. why should you be concerned? the u.s.a could get involved and casue more damage, also russia is supporting the syiran government if the us gets involved it could cause a bigger conflict hope this helps
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From a state of endangerment, many languages become extinct. When the speakers of a language are exterminated as what happened to Tasmanians in the 19th century, several languages suddenly died. Another reason for the extinction is the pressure exerted on a community to incorporate with a more powerful or larger group.
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The age of the rock = 2800.6 million years = 2.8 billion years.
A simple method of analysis similar to Carbon dating is used to obtain the required age of the rock. Radioactive substances decay according to first order reaction kinetics. So, plugging all the required parameters into the general equation for amount of substance left in a first order decay gives us the age of the rock.
Explanation:
Half life of Uranium-235 = 700 million years (from literature)
The decay of radioactive substances follow first order reaction kinetics.
The general equation is given as
A(t) = A₀ e⁻ᵏᵗ
A(t) = Amount of radioactive substance left after a particular time = 6.25%
A₀ = initial amount of radioactive substance = 100%
t = time that has passed since the beginning = age of the rock = ?
k = decay constant
The decay constant is related to the half life (T) through the relation,
k = (In 2)/T
k = (0.693/700) = 0.00099 /million years
A(t) = A₀ e⁻ᵏᵗ
6.25 = 100 e⁻ᵏᵗ
0.0625 = e⁻ᵏᵗ
In e⁻ᵏᵗ = In 0.0625 = -2.7726
-kt = - 2.7726
t = (2.7726/0.00099) = 2800.6 million years
t = 2.8 billion years.
Hope this Helps!!!
