<span>If Charles leaves the marina and sails his boat 10° west of north for 1.5h at 18km/h, then makes a right turn towards 60° east of north for 1.2h at 20km/h, he is 42 km from his starting point.</span>
You mean a square has an AREA of 100 square meters? The length of 1 side equals square root of 100 = 10 meters. Therefore perimeter = 4 * 10 = 40 meters.
