<span>All physical forms of water:solid, liquid, and gas on or near the earth's surface make up the HYDROSPHERE</span>
Answer:
B. Death Valley, CA
Explanation:
Here are the elevations of each location:
Key West, Florida 18 feet
Death Valley, California -282.2 feet
Seattle, Washington 175 feet
Corpus Christi, Texas 7 feet
Because Death Valley sits at -282.2 feet below sea level, the lowest elevation, <u>B is the answer</u>.
Tip: Without knowing the exact elevations of each location, we could assume that a <em>valley</em> would be lowest.
C . Telegraph ..............
The answer is C because Burma is rich with its resources that no one pays attention to the human rights
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!!!
