There are multiple devices that emit radio waves. The most obvious is are radiod and microwaves (yes, the food cooker). Wireless applicances also emit radio waves. But don't confuse everything to use microwaves. Some applicances use frequencies instead of radio waves. Some applicances that use frequencies are toy control remotes and a garage door.
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Uhhhh I believe it’s true if it’s wrong I’m srry ....
a hard copy stores data and information in the form of physical files it may be images text photographs and more a soft copy data and information in the form of virtual file saved on a computer or a drive you can preserve a hard copy for two long because its day subjected to wear and tear