As the speed of river water slows what is deposited

Sediment. So the river picks up sediment when it is moving quickly and deposits it when it slows down (or when there is a bend in the river).

Sorry its not enough info

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