Answer:
The last one is false
Explanation:
Energy can be neither created or destroyed. It can only move from one type of energy to another.
The answer is D. Isotopes.
Hope that helped.
<span>If 1 eighth equals 1 billion 7 eighth equals 7 billion.
The asker of the second question needs a tutorial in radiometric dating. There is little likelihood that the daughter isotope has the same atomic weight as the parent isotope. To measure the mass isotopes doesn't tell us how many atoms of each exist. To get around that let's pretend — which will likely serve the purpose ineptly intended — that the values give an the particle ratio, 125:875.
The original parent isotope count was 125 + 875 = 1000. The remaining parent isotope is 125/1000 or 1/8. 1/8 = (1/2)^h, where h is the number of half-lives.
h = log (1/8) ÷ log(1/2) = 3
And 3 half-lives • 150,000 years/half-life = 450,000 years.</span>
'Frequency' is a word that often confuses some people ... for no good reason.
It just means "frequent-ness" or "often-ness" ... how often something happens.
The SI unit of frequency is the Hertz (Hz). Hz means 'per second'.
So " 13 Hz " means 13 per second.
Here are examples of frequency:
-- 780 kilohertz (on your AM radio dial)
-- 98.7 Megahertz (on your FM dial)
-- 5.8 Gigahertz
-- twice a day
-- three per week
-- every 6 months
1) Frequency: 
The frequency of electromagnetic radiation is given by:
where
is the speed of light
is the wavelength
In this case, the wavelength of the radiation is
Therefore the frequency is
2) Period: 
The period is equal to the reciprocal of the frequency of the wave:
Using the frequency we found previously, 
, we find:
