In Example 3.1.3 in Section 3.1, a box with no top is constructed from a 10 inch × 12 inch piece of cardboard by cutting out congruent squares from each corner of the cardboard and then folding the resulting tabs. We determined the volume of that box (in cubic inches) is given by V(x)=4x3−44x2+120x, where x denotes the length of the side of the square which is removed from each corner (in inches), 0<x<5. Solve the inequality V(x)≥80 analytically and interpret your answer in the context of that example.