E9A02 - Amateur Extra Class

E9A02 : What is the effective radiated power (ERP) of a repeater station with 150 watts transmitter power output, 2 dB feed line loss, 2.2 dB duplexer loss, and 7 dBd antenna gain?
A 469 watts
B 78.7 watts
C 420 watts
D 286 watts
Correct Answer: 286 watts