The significance of the arrangement of bones in a human arm and a bat wing is that humans and bats share a common ancestor.
This is what e=mc² means.
So rest energy is RH side of equation that is its mass times speed of light squared.
On October 4, 1957, Soviet satellite Sputnik, the world's first artificial satellite, blast into space and transmitted information via radio signals to Soviet scientists for three weeks. Sputnik II was launched in November 1957 with a a dog called Laika aboard.
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