Calculating the force of friction on an object

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purplecows
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Homework Statement


A 40.0-kg object is being pulled along a horizontal surface by means of a rope that exerts a force of 200 N at an angle of 30° below the horizontal. The coefficient of static friction between the object and the surface is 0.40. The force of friction on the object is:
A) 197 N
B) 173 N
C) 392 N
D) 157 N

Homework Equations


µ_s = F_s/ F_n

The Attempt at a Solution


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So I got 197 N, which was A. However, the answer was B on the answer sheet. What have I done wrong?
 
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The answer is B and it's correct.

There are a lot of red herrings in this problem! I fell for the "static friction" coefficient myself.

The force is already given, so things like friction coefficients and mass are irrelevant.
 
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