What is a primary function of fiber-optic cables?

magnifying distant images
cutting through metals
carrying signals at high speeds
performing high-precision surgery

Explanation:

Carrying signals at high speeds

Fiber optics (optical fibers) are large, thin strands of extremely pure glass about the breadth of a human hair. They are organized in packages described as optical cables which are utilized to transfer light signals over long distances. Moreover, Fiber optic Internet transfers data faster than  any ordinary cable.

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Carrying signals at high speeds

Fiber optics (optical fibers) are large, thin strands of extremely pure glass about the breadth of a human hair. They are organized in packages described as optical cables which are utilized to transfer light signals over long distances. Moreover, Fiber optic Internet transfers data faster than  any ordinary cable.

measuring things 1 litre of water

if the person is shown to have +90n, then ans is -10n.

if the person is shown to have -90n, then ans is +10n.