1. The problem statement, all variables and given/known data draw the eye diagram you would expect to see should a digital signal be passed through a transmission line with a bandwidth limited to three times the maximum bit rate of the digital signal. the answer is "Only f1 and f3 pass through" My question is, what about f2 ? Why does the answer to this question read f1 & f3 rather than f1 - f3 (including f2) ? Thanks for any clarification.