So that we do not contaminate it with microorganisms or garbage or other human stuff.
It's been a while since I've studied this, but my answers would be:
13. 5730 years. The half-life of a substance is the amount of time it takes for half of it to decay, and, according to the graph, half of the substance remained at 5730 years.
14. 10740 years. According to the graph, only 25% of the carbon remained after 10740 years.
15. 15 atoms. According to the graph, only 12.5% of the carbon remained after 16110 years. 12.5% of 120 atoms is 15 atoms.
16. 1600 atoms. According to the graph, if a sample of carbon is 10740 years old, only 25% of it remains. To find the original amount, multiply the current amount by (100% / 25%), which equals 4. So, 4. 400 atoms * 4 = 1600 atoms is the original amount.
For a standing wave on a string, the wavelength is equal to twice the length of the string:

In our problem, L=50.0 cm=0.50 m, therefore the wavelength of the wave is

And the speed of the wave is given by the product between the frequency and the wavelength of the wave:
Answer:
Explanation:
a = 4ms⁻², Vf = 180 m/s & Vi = 140m/s
a =
4 = 
t = 40/4
t = 10sec
To Measure Distance Use third Equation of Motion:
2aS = Vf²-Vi²
S = 
S = 12800/8 = 1600m
Concentrated solar power facilities are solar power—generating facilities that generate electricity at large centralized facilities and transmit that power to homes and businesses through the electric grid .
<h3>What is solar power?</h3>
Solar power refer to electric power or electricity that is generated from sun rays or radiations while using solar panels and other technologies.
Therefore, Concentrated solar power facilities solar power—generating facilities that generate electricity at large centralized facilities and transmit that power to homes and businesses through the electric grid.
Learn more about solar power below
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