Compton observed an increase in wavelength with scattered X rays, which meant that the X-ray photons had a. lost momentum only.
b. lost both energy and momentum.
c. gained energy only.
d. gained both energy and momentum.

spectral lines lyman is one set

the working equation for the angular size is the product of the physical size and 360 degrees divided by the product of two pi and distance from earth. the minimum size would be 0.559 degrees while the maximum size would be 0.49 degrees. 

that tool is called an altimeter which measures your altitude which can be used to tell which atmosphere you are currently in, including the stratosphere.

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