What is radio wave?
A. radio waves have the longest wavelength in the electromagnetic spectrum
B. radio waves have very limited range of wavelengths
C. radio waves are produced by making protons vibrate in an antenna
D. radio waves have smaller wavelengths than microwaves
All the following are disadvantages of radio waves, except
A. more costly than infrared
B. it is easier to "eavesdrop" since signals are transmitted in space rather than a wire
C. communication devices that make use of the same frequencies interfere with their transmission
D. low power requirements that makes it ideal for laptops, and other technological devices