If twice the length of A passes a stationary point every second, what is the frequency of the wave?

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?

Several mountains together form a mountain . a few of these combined form a mountain system. several systems combined form a mountain , which can stretch thousands of miles in length.

In a voltaic cell, electrons flow from the (positive/negative) to the (positive/negative) terminal.