Answers please and thank you

From center station, a train departs every 30 minutes on the fast line and a train departs every 50 minutes on the state line. if two trains depart from center station at 8: 00 a.m., one on each of the two lines, what is the next time that two trains, one on each line, will depart at the same time?

What is a carrier wave and how does it affect what you hear on the radio

The discovery of the electron as a subatomic particle was a result of