Answer:
Formula for area of a trapezoid:
a = h(b1 + b2) x 1/2
let's plug in the values for the left trapezoid;
a = 14(9 + 16) x 1/2
a = (126 + 224) x 1/2
a = 350 x 1/2
a = 175
now for the right trapezoid;
a = 15(11 + 17.5) x 1/2
a = (165 + 262.5) x 1/2
a = 427.5 x 1/2
a = 213.75
Now let's add both of their sums:
175 + 213.75 = 388.75
But now we need to find the cost, so we multiply the cost with the total sum;
388.75 x $1.7 = 660.875, around $660.88