Can someone please help me out

Compare these two waves: the blue and orange waves have the same pitch, but the blue wave is louder. the blue and orange waves have the same volume, but the blue wave has a higher pitch. the orange wave has a higher pitch, but the blue wave is louder. the blue wave has a higher pitch, but the orange wave is louder.

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

Solve each quadratic equation by factoring and using the zero product property. n^2 - 49 = 0