Answer:
Transmitters send radio waves, and receivers capture radio waves.
Explanation:
Let us look at each of the choices one by one:
(1).Transmitters have antennas, and receivers do not have antennas.
Nope. To send signals transmitters need antennas, and to receive signals the receivers need antennas as well.
(2). Transmitters send radio waves, and receivers capture radio waves.
This is true. Transmitters are for transmitting and receivers are for receiving EM signals.
(3). Transmitters have demodulators, and receivers have modulators.
No, it is the other way around. Transmitters have modulators, and receivers have demodulators.
(4). Transmitters do not have amplifiers, and receivers have amplifiers.
Nope. Both the transmitters and the receivers need amplifiers. Transmitters need them to increase the power of the broadcast, and receivers need them to amplify the signal for processing.
Therefore, only the 2nd statement "Transmitters send radio waves, and receivers capture radio waves." is correct.
= characteristic wavelength = 9 μm = 9 x 10⁻⁹ m