From the list below, select all the astronomical sources whose study is greatly advanced by using the Doppler Effect. the rotation curve of the Milky Way merging black holes identification of...

Pls help ASAP. Pls show all work. Pls do both.

Extracted text: From the list below, select all the astronomical sources whose study is greatly advanced by using the Doppler Effect. the rotation curve of the Milky Way merging black holes identification of volcanoes on lo | exoplanets binary pulsars | eclipses single-line spectroscopic binaries


Extracted text: During main-sequence hydrogen burning, in what direction on a Hertzsprung-Russell diagram does a G star move? Up and to the right Down and to the right Up and to the left Down and to the left AG star would NOT move on the HR diagram during main-sequence hydrogen burning