How many minutes would it take for a radio wave to travel from the planet Venus to Earth? (Mean distance from Venus to Earth = 28 million miles). 

4. The blue color of the sky is due to the scattering of sunlight by air molecules. Blue light has a frequency of approximately 7.5 x 1014 Hz. Calculate the wavelength, in nm, associated with this radiation. 

5. Calculate the frequency and energy of blue light that has a wavelength of 400 nm. 

6. First calculate the frequency of light that has a wavelength of 4.25 x 10-9 m and second identify the type of electromagnetic radiation.