<div>Please advise if any of the following validations may be improved, and/or any part of the codes may be shortened?</div><div><br></div><div>&lt;?php</div><div><br></div><div>// Check if form was submitted</div><div>if(isset($_POST['submit'])) {</div><div><br></div><div><span style="white-space:pre"> </span>// Configure upload directory and allowed file types</div><div><span style="white-space:...