Solve the given question:
Question: In the human arm, the forearm and hand pivot about the elbow joint. Consider a simplified model in which the biceps muscle is attached to the forearm 3.80 cm from the elbow joint. Assume that the person's hand and forearm together weigh 15.0 N and that their center of gravity is 15.0 cm from the elbow (not quite halfway to the hand). The forearm is held horizontally at a right angle to the upper arm, with the biceps muscle exerting its force perpendicular to the forearm. Assume that the center of gravity of this weight is 33.0 cm from the elbow. While holding the 80.0-N weight, the person raises his forearm until it is at an angle of 53.0 degree above the horizontal.
Part A: If the biceps muscle continues to exert its force perpendicular to the forearm, what is this force when the forearm is in this position?
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