Hl. i just need the diagraam i can't figure it out. surveyor is measuring the length of a lake. he takes angle measurements from two positions, a and b that are 136 m apart and on the same side of the lake. from b, the measure of the angle betweet the sight lines to the ends of the lake is 130 degrees and the measure of the angle between the sight lines to a and one end of the lake is 120°. from a, the measure of the angle between the sight lines to the ends of the lake is 65 degrees, and the measure of the angle between the sight lines to b and the same end of the lake is 20 degrees calculate the length of the lake, to the nearest metre. 20°..