Use technology to maximize the following. You may round answers to 2 decimal places if desired.
Maximize $f = 4x + 7y + 8z$ subject to
$3x + 2y + 5z \le 30$
$3x + y + 4z \le 28$
$2x + y + 3z \le 12$
$x \ge 0, y \ge 0, z \ge 0$
If no solutions exist enter DNE in all answerboxes.
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