Round off 4518 to the nearest thousand. Then estimate the value below. <br> 4518 x 9 <br>≈ <input min="0" type="number" id="imp5pg003q10c_1" class="lineinput" placeholder="?"> x 9 <br>= <input min="0" type="number" id="imp5pg003q10c_2" class="lineinput" placeholder="?">