A trapezoid’s area can be calculated by the formula \(A=\frac{1}{2}(b_1+b_2)h\text{,}\) where \(A\) stands for area, \(b_1\) for the first base’s length, \(b_2\) for the second base’s length, and \(h\) for height.

Use the formulas to calculate the trapezoid’s area. Its first base’s length is \({18\ {\rm m}}\text{,}\) its second base’s length is \({9\ {\rm m}}\) and its height is \({11\ {\rm m}}\text{.}\)

Area =