Peggy delivers pizzas. she left the pizza parlor this evening and traveled 4 km east to deliver a pizza to the red house. then she left the red house and traveled 8 km south to the blue house. then she left the blue house and traveled 4 km west to the yellow house, she traveled 2 km north to the green house. she now wants to return to the pizza parlor. what is the shortest distance between the green house and the pizza parlor?