It is 3.2 because you add 2.3 and 4.1 then divide your answer by 2.
The force of friction is 78.4 N
What is force of friction?
Frictional force is the force created when two surfaces come into contact and slide against each other. it is given by the equation:
μ * 
where,
= force of friction
μ = coefficient of friction
= normal force
Given,
μ 
We know,


Subsituing the values in equation:
μ * 

The force of friction is 78.4 N.
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