Haven't taken physics but I would assume if her friend is standing in front of her that you would add up the speeds and get 30 km/hr.
Answer:
2.3 Nm clockwise
Explanation:
Take counterclockwise to be positive and clockwise to be negative.
∑τ = (3 N) (2.5 m) − (7 N) (1.4 m)
∑τ = 7.5 Nm − 9.8 Nm
∑τ = -2.3 Nm
The net torque is 2.3 Nm clockwise.
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