Answer:
The wide is 70.02 m.
Step-by-step explanation:
First you need to draw a triangle with only one 90 degrees angle.
The opposite side to the 90 degrees angle will be the hypotenuse.
We will call the remaining sides ''Baseline'' and ''River wide''.
The angle between hypotenuse and baseline is 35 degrees.
The triangle has one 90 degrees angle so we can apply the tangent equation
in the angles that are no 90 degrees.
Tangent (angle) = Opposite side/adjacent
Tan(35°)= River wide/100m
River wide = 100m.Tan(35°)
River wide = 70.02 m