The H _- Line Has a Wavelength of 434

Multiple Choice

The H _- line has a wavelength of 434.0 nm when observed in the laboratory.If the H _- line appears in a stars spectrum at 434.5 nm,what is the radial velocity of the star?

A) 346 km/sec away from the observer
B) 346 km/sec toward the observer
C) 1.3*10⁸ m/sec away from the observer
D) 1.3*10⁸ m/sec toward the observer
E) The radial velocity of the star can not be determined from this information.