A high tech company operates a satellite which can measure the size of features on the surface of the earth. They use this technology to measure a particular rectangular field and find it's length to be 311 \pm± 1.89 (in meters) and it's width to be 354 \pm± 1.39 (in meters). They plan to report the area of the field as A\pm\Delta AA ± Δ A in units of acres. (1 acre = 4840 square yards & 1 meter = 1.094 yards) What is \Delta AΔ A?