To type the squared subscript, type the number 2. Then highlight it with your cursor. Then click the CTRL and the SHIFT key. When the options pop up, click the "x 2" option to have the 2 change to a subscript. Ex: 34 ft2 turns into 34 ft2
92 ft2
54.88 m2
53.86 cm2
71.44 yd2
25 in
132 m2
121.12 ft2
128 in2
69 cm2
53.12 ft2
63 m2
108 yd2