The frequency of a sound is whatever frequency leaves the source. It doesn't change.
Voiced of swimmers at the pool don't change frequency in or out of the water. Only their speed and wavelength change.
Answer:
The frequency , speed and wavelength of an electromagnetic wave are related by the formula
Speed = frequency x wavelength
frequency = speed / wavelength
substituting the values
frequency = 3 x #10 ^8# m /s / 1 x #10^15# m
= 3 x #10^-7# /s
Check the picture below.
now, for 6 triangles, well, simply 6*6.
