The mass of the rider 1 is 4 g.
<h3>
The use of a rider in mass measurement</h3>
Rider is a metallic wire piece which is of certain mass and can be bent . It can move the beam of the Paul Bunge Balance.
The riders are the sliding pointers positioned on top of the beams to show the pan and beam weight in grams.
<h3>Mass of the rider 1</h3>
The mass of the rider 1 is obtained by subtracting mass of riders as show below.
mass of rider 1 = mass of object - (mass of rider 2 + mass of rider 3)
mass of rider 1 = 694 g - (600 g + 90 g)
mass of rider 1 = 694 g - 690 g
mass of rider 1 = 4 g
Thus, the mass of the rider 1 is 4 g.
Learn more about use of riders in mass measurement here: brainly.com/question/1747339
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