How fast does electromagnetic radiation move through space? What is this called?​

How would doubling the made of an object change the objects potential energy

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?

Under normal conditions, describe how increasing the temperatures effects the solubility of a typical salt