Brunette Girl Posing On The Mirrors

If there are two people, one person can hold their arm so that it points at the target. The signaler, holding the mirror as close to their eyes as possible, so as not to confuse their perspective with that of the mirror, can then see the light moving straight along the arm and directly at the target. Or if this isn't possible, improvise. A clear head in emergencies is the most essential of safety devices.
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