Two starships, the Enterprise and the Constitution, are approaching each other head-on from a great distance. The

Question:

Two starships, the Enterprise and the Constitution, are approaching each other head-on from a great distance. The separation between them is decreasing at a rate of 782.5 km/s. The Enterprise sends a laser signal toward the Constitution. If the Constitution observes a wavelength λ = 670.3 nm, what wavelength was emitted by the Enterprise?