An alien spaceship is 8*10^14 m away sends us a radio wave signal. how long does it take for the signal to reach us?

You notice a very one-dimensional-thinking snail crawling along one rail of a railroad track. naturally, you remove it to a safer place. but before you do, you observe it as it moves from position xi = -92.9 cm to position xf = -64.9 cm along the rail, as measured from a point where one rail abuts the next. what is the snail\'s displacement δx in centimeters?

In a system, when potential energy decreases, then entropy also decreases. true false

Which of the following are used in an electrochemical cell? a. electrodes b. electrolyte c. terminals d. all of the above