An axial load P is supported by a short W8 X 40 column of a cross-sectional area A = 11.7 in2 (inches squared) and is distributed to a concrete foundation by a square plate as shown (in the attachment) Knowing that the average normal stress in the column must not exceed 35 ksi and that the bearing stress on the concrete foundation must not exceed 3.5 ksi, determine the side a of the plate that will provide the most economical and safe design.