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3 years ago

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What is a highland? (A) An area of high or hilly land (B) A piece of land surrounded by water on three sides (C) A large area of

land made up of one type of landform (D) A raised, flat-surfaced area bound on one or more sides by cliffs Also, I don't think this is a Physics question, it is just 6th-grade science.

2 answers:

kozerog [31]3 years ago

8 0

Answer: Option A

Explanation:

A highland, as the name implies, is an extension of mountainous land.

So a highland is any region that is "elevated" compared with the surrounding region.

With this definition, the correct option is A: An area of high or hilly land (obviously, high or hilly compared with the surrounding area)

Karolina [17]3 years ago

3 0

Answer:

A

Explanation:

A Highland is an area of mountains.

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Answer:

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Explanation:

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Given that a sample decay 1% per day, that means that after first day you have 99% of mass.

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Question#7:a) A television uses 1500J of electric energy to produce 1100J 1 point

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Answer:

a.73.3%

b.26.6%

Explanation:

a. The efficiency is the energy output, divided by the energy input, and expressed as a percentage.

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b. From a above, we know that the TV has an output of 1100J and input of 1500J.

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3 years ago

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Answer:

The age of living tree is 11104 years.

Explanation:

Given that,

Mass of pure carbon = 100 g

Activity of this carbon is = 6.5 decays per second = 6.5 x60 decays/min =390 decays/m

We need to calculate the decay rate

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Where, N = number of radio active atoms

$t_{\frac{1}{2}}$ =half life

We need to calculate the number of radio active atoms

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Where, $N_{A}$ =Avogadro number

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For $N_{c_{14}}$

$N_{c_{14}}=1.30\times10^{-12}N_{12_{c}}$

$N_{c_{14}}=1.30\times10^{-12}\times5.02\times10^{22}$

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Put the value in the equation (I)

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$R=100\times15.0650=1507\ decay/min$

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$2^n=\dfrac{1507}{390}$

$2^n=3.86$

$n ln 2=ln 3.86$

$n=\dfrac{ln 3.86}{ln 2}$

$n =1.948$

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Using formula of age

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