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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)

Express the following as a function of a single angle. cos(60) cos(-20) - sin(60) sin(-20)

Pranza plotted point a in the coordinate plane below.