Answer: The real tree house door should be 126 cm tall.
Explanation:
Given: Two students make a model of a tree house they want to build. The scale is 1:42.
i.e. 1 cm of model = 42 cm in real
if the in the scale model,the door is 3 cm tall, then the height of real tree house door = 3 x (42) cm
⇒ Height of real tree house door= 126 cm
Hence, the real tree house door should be 126 cm tall.
Olympia is the capital of Washington
Answer: Canada may be divided into seven physiographic regions: Arctic Lands, Cordillera, Interior Plains, Hudson Bay Lowland, Canadian Shield Forest Lands, St Lawrence Lowlands and Appalachia. Divisions are based on each area's relatively similar physical geography and landforms.
Explanation:
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:
Our culture represents our traditions, our history, our celebrations, our holidays, food, ancestry, and race.
Explanation: Think about your culture. What is your history? Your ancestry? Your traditions and celebrations?
I hope this helped. Have a nice day.
