When visiting some countries, you may see a person balancing a load on the head. explain why the center of mass of the load needs to be directly above the person’s neck vertebrae.

Explanation:

If the center of the load is directly above the vertebrae, there is no torque in the system. This is a good thing so that the vertebrae are not put out of alignment over time. (Of course, this still doesn't prevent compression of the vertebrae over time, which is a possibility.)

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this would be about 43%