A carpenter uses sandpaper on a piece of wood. Before, the wood felt rough. After, the wood felt smooth. Did the friction between the hand and the wood increase or decrease after using the sandpaper?
Describe what the sandpaper did to the wood to make it smoother.

The soviet union beat the us to the first successful launch, with the october 4, 1957, orbiting of sputnik 1, and later beat the us to have the first human in earth orbit, yuri gagarin, on april 12, 1961. the "race" peaked with the july 20, 1969, us landing of the first humans on the moon with apollo 11