How can you make a bitmap fade from 100 percent opacity to 0?

Question

Accepted Answer

By attaching a mask then setting the gradient tool from 100 percent opacity to 0 and applying the gradient to the mask

Answer

By converting it to a vector image then setting the gradient tool from 100 percent opacity to 0 and applying the gradient to the mask

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By converting it to a smart object then setting the gradient tool from 100 percent opacity to 0 and applying the gradient to the image

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Once a selection has been made - adjust the feather in the Properties panel

Answer

By attaching a mask then setting the gradient tool from 100 percent opacity to 0 and applying the gradient to the image