suppose each trial equals 1,000 years. after half 50 of the virtualium cubes were removed from the box, about how long did it take for half of the rest of the cubes to decay?

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

Ibelieve is d but i’m not 100% sure