V=wavelength×frequency
1. wavelength=13/12 km
speed= 18×8 = 144mm/s
<span>A lot of things take up electricity. Just leaving something plugged in can cost energy that could have been used for something more worth while. I think the biggest thing people do that wastes energy is that we leave lights on when we don't need them. I would like to improve this method by turning my lights off everytime I exit the room or by not even turning on the light if I can see without it. If it is daylight outside and you have a window in the room and you can see perfectly fine without the light, then why turn it on? No one ever thinks about that. Leaing our lights on is a common factor that raises our light bills. We always think we are gonna come back into the room in a minute but it ends up being a hour later. That's valuable money down the drain because no one is in the room using the light.
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Observation– the process of using the five senses to gather information
