At the low temperatures found in some interstellar molecular clouds (around 100 K), molecular oxygen emission is strongest at a wavelength is 0.2521 cm. Determine the speed (in km/s) of a low temperature molecular cloud containing molecular oxygen if its strongest emission is at a wavelength of 0.1875 cm. This cloud is moving towards us, so your answer should be negative.

Only enter your numerical answer below - do not include units.Report your answer to 2 decimal places.