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How is sound energy produced a. vibrating objects b. objects being heated c. temperature differences d. stationary objects

Suppose a comet has an orbital period of 309.1 years around the sun. what is it’s average distance from the sun?

Hydrogen atoms are excited by a laser to the =4n=4 state and then allowed to emit. what is the maximum number of distinct emission spectral lines (lines of different wavelengths) that can be observed from this system? 8 6 2 7 4 5 1 3 calculate the wavelength of the 4⟶14⟶1 transition. =λ=