What is the purpose of using scales in drawings?

A drawing that shows a real object accurate sizes reduced or enlarged by a certain amount. The scale is shown as the length in the drawing.

It was crowded with sewer like smells. bad sewer systems

The boat's velocity relative to the riverbank can be resolved into two components. the component going north is 2.7 m/s and the component going west is 1.2 m/s.we add these two vectors and then find the magnitude of the resultant to get the speed.the magnitude of the resultant vector from adding can be obtained by the pythagorean theorem.    to two significant figures, the boat's speed relative to the riverbank is 3.0 m/s.