Hi,
Easy peasy, reach your arm around the window when open, sometimes you will need the small Unger extention pole, about 8" inches. Or with the small Ettore extention pole 24"to 48" inches reach the outside of the end window when closed from the one at the other end when open.
To save sitting on the window sill which inproves reach I carry a 2 step step ladder.
Kevin WINDOLENE.