In fact it is easier than that (and the diffucult part is to decide on , or )
current density = current + density
I hope OP understand the english meaning of both the terms ?
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Fantastic ideas for a Fantastic World, I make the illogical logical.They put me in cars,they put me in yer tv.They put me in stereos and those little radios you stick in your ears.They even put me in watches, they have teeny gremlins for your watches