Answer:
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!!!
Answer:
Interestingly, many French maps showed zero degrees in Paris for many years despite the International Meridian Conference’s outcomes in 1884. GMT was the universal reference standard – all other times being stated as so many hours ahead or behind it – but the French continued to treat Paris as the prime meridian until 1911. Even so, the French defined their civil time as Paris Mean Time minus 9 minutes and 21 seconds. In other words, this was the same time as GMT.
In 1972, Coordinated Universal Time (UTC) replaced GMT as the world's time standard. France did not formally use UTC as a reference to its standard time zone (UTC+1) until August in 1978.
Standard time, in terms of time zones, was not established in United States law until the Act of March 19, 1918. The act also established daylight saving time in the nation. Daylight saving time was repealed in 1919, but standard time in time zones remained in law, with the Interstate Commerce Commission (ICC) having the authority over time zone boundaries.
Many countries started using hourly time zones by the late 1920s. Many nations today use standard time zones, but some places use 30 or 45 minute deviations from standard time. Some countries such as China use a single time zone even though their territory extends beyond the 15 degrees of longitude.
C: Ecosystem 1
Because there’s not a lot of diversity in only 10 species, making it easy to wipe out the entire population.
Answer:
It demonstrates the role that Islam played in the rise of large, powerful civilizations in Africa.
Explanation: Islam has played a massive role in North african countries economies. Less Corruption and egypt is one of those 3rd world countries that is moving up in level faster than any other african country