Note that different people have different research approaches. The two old ladies check that none of them can see herself and the problem is solved! ;-)
The other older lady makes an experiment with motion and rigorously determines that she is ... well ... unsichtbar. :-)
Zuckerberg: Internet Growth Means More than Drones - Efforts to expand Internet access via mobile technologies may be stymied by economic and social challenges. Mark Zuckerberg said today at Mobile World Co...
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