Is it possible to measure area using Google Earth?

Yes. google Earth Professional also allows you measure area, but it is expensive. Alternatively you can use the free version of google Earth, mark the area to be measured as a path. Then save it as a kml file. Programs like EasyAcreage can then read these kml files and calculate the acreage for you. This method is remarkably accurate. See a case study where the accuracy of this method was used to measure the size of a tennis court.

The KML Tools Project and Zonums area tool (in links below) is an easy way to measure area online.