Yes, every time you compress the jpg again it will lose quality because jpg is a lossy format (Someome else already explained the difference between lossy and lossless) but putting it in a zip won't compress it again. Since zip compression is lossless no data is lost, so you can decompress and recompress as often as you want without losing data. Same goes for png, it's lossless too. Recompressing a jpg as a png (E.g. by opening it in a photo editor and saving at as a png) doesn't make sense tho, the data was already lost when saving as jpg, so the jpg and the png will be the exact same picture. The png will just be a lot bigger in size.
Yes but png or jpg files take the data of an image and save them in a more efficient way inside a file. A zip file takes any file and saves it in a more efficient way. Putting a png inside a zip will compress the compressed image file but since zip compression is lossless, you'll get the the exact same compressed image file back when you decompress the zip again. Same goes when putting a jpg file inside a zip.
A file does not deteriorate and you can't just change extension to change the file type. Jpgs are fine
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Yes, every time you compress the jpg again it will lose quality because jpg is a lossy format (Someome else already explained the difference between lossy and lossless) but putting it in a zip won't compress it again. Since zip compression is lossless no data is lost, so you can decompress and recompress as often as you want without losing data. Same goes for png, it's lossless too. Recompressing a jpg as a png (E.g. by opening it in a photo editor and saving at as a png) doesn't make sense tho, the data was already lost when saving as jpg, so the jpg and the png will be the exact same picture. The png will just be a lot bigger in size.
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Yes but png or jpg files take the data of an image and save them in a more efficient way inside a file. A zip file takes any file and saves it in a more efficient way. Putting a png inside a zip will compress the compressed image file but since zip compression is lossless, you'll get the the exact same compressed image file back when you decompress the zip again. Same goes when putting a jpg file inside a zip.