Q. The available power required at a receiving antenna is 106 Watts. Transmitting and receiving antennas have gain of 40 dB each. The carrier frequency is 4 GHz and the distance between them is 30 miles. The required transmitter power is ?

• (A) 0.64 W
• (B) 0.74 W
• (C) 0.78 W
• (D) 0.32 W