Guess the rendering engine

Given the following block of CSS, which rendering engine goes with which number?

p {
    clear: both;
    margin: 1em;
}
p:first-child:first-letter {
    display: block;
    float: left;
    font-size: 3em;
    font-style: italic;
    line-height: .7em;
    text-indent: .2em;
    text-shadow: 4px 4px 3px #000;
    width: 1em;
}

Hint: four rendering engines shown, but one has two versions represented, since they have drastically different CSS support.

P.S. Any graininess stems from image optimization rather than browser rendering.