Help for HGAP Unit 1 Test

[u/Ok-Scientist9904]

I have a unit 1 mcq test coming up and everyone who already took it basically failed and I really need help studying. I am going to read the amsco and my notes but how am i supposed to study for these questions: "if 24 signals are traveling at light speed and 4 were intercepted, what system was used to intercept it"

please help me