I think so it ans wold be d.because if the source approaches the observer more and more wavefront will pass and it get squeezed.so wavelength decreases and frequency increases.
-- Multiply each side of the formula by 2
-- Then divide each side by t
-- Then subtract V(i) from each side.
Answer:
NASA's Chandra X-ray Observatory and other telescopes such as the Hubble telescope.
Explanation:
Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies.
The above observations have provided the strongest evidence yet that most of the matter in the universe is dark.
