D. <span>Johannes Kepler argued that Earth was the center of the universe.
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Speed = (frequency)x(wavelength).
Frequency = 6 Hz
Wavelength = 9mm = 0.009m.
Speed = (6 Hz) x (0.009m) = 0.054 m/s or 54 mm/sec.
The answer is 266. Hope that helps!
Dimensional analysis is a method of checking the dimensions of each value in an equation. I will give you an example.

Is a know equation which equates energy and mass. So our question is, is this true or not? The method is following:
knowing that c has the dimension of [m/s] and m has [kg], what is the dimension of E? So here the dimensional analysis begins.
![E = mc^2 \Rightarrow [E] = \text{kg} \cdot \left( \frac{\text{m}} {\text{s}}\right)^2 = \text{kgms}^{-2}](https://tex.z-dn.net/?f=E%20%3D%20mc%5E2%20%5CRightarrow%20%5BE%5D%20%3D%20%5Ctext%7Bkg%7D%20%5Ccdot%20%5Cleft%28%20%5Cfrac%7B%5Ctext%7Bm%7D%7D%20%7B%5Ctext%7Bs%7D%7D%5Cright%29%5E2%20%3D%20%5Ctext%7Bkgms%7D%5E%7B-2%7D)
This can be used also to solve "equations" to prove certain dimensions of unknown constants.
Answer:
Chemical energy
Explanation:
Batteries are chemical energy because its a bunch of little reactions causing the batteries to work