If the peak wavelength of a star at rest is 830 nm, but astronomers on earth observer that is has been shifted by 3.2 nm. Then how fast is the star moving relative to the earth?

The chart shows the amount of solute that fully dissolved when added to 500 ml of water. which ranks the solutions in order of greatest to least solubility? x → y → z y → x → z z → x → y y → z → x