Which point could be removed in order to make the relation a function? {(–4, 3), (–5, 6), (1, 0), (–4, 5), (9, 5), (0, –7)}

If the speed of an electromagnetic wave is 100,000 cm/s and its wavelength is 100 cm, what is its frequency? a) 100,000 cycles per second (hz) b) 1 × 10-3 cycles per second (hz) c) 10,000,000 cycles per second (hz) d) 1,000 cycles per second (hz)