A ground station on Earth transmits a signal of frequency 
and power 
towards a communications satellite orbiting the Earth, as illustrated in the figure below.
The loss in signal power between the ground station and the satellite is 
.
Calculate the power of the signal received by the satellite.
The signal received by the satellite is amplified and transmitted back to Earth.
Suggest a frequency for the signal that is sent back to Earth.
Give a reason for your answer in (i).
.
or 
.
