An astronomer who wishes to photograph the light spectrum would use a: spectrograph radio telescope refracting telescope reflecting telescope

spectrograph

Explanation:

A spectrograph is a apparatus that divides the incident light from an object into a frequency spectrum and measures the amount of radiation at every wavelength by dispersing radiation into a spectrum and also records it.

Therefore, An astronomer who wishes to photograph the light spectrum would use a spectrograph.

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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