Clicking on the measure tool will open a window with three measure options: straight line, free line and polygon.
Clicking on the Line icon will allow you to draw a straight line on the map. The Measure Tool will provide then the measurement of your line in feet and miles. Clicking on the Clear icon will remove the line and the measurements. Clicking on the free line will allow you to draw a free line on the map and will also provide measurements in feet and miles of your line. Finally, clicking on the Polygon icon will allow you to draw a polygon. Measurements will be calculated in square feet, acres, square miles and miles around the perimeter.