The number next to 2, which is in the thousands place, is 0 and since the rule for rounding any number less than 5 is to round down, you would round 102,011 to 102,000 for the nearest thousands place.
Because it takes 5730 years for half of a sample of carbon-14 atoms to decay. It says that 50% of the carbon atoms have decayed so that means that 5730 years have elapsed for that fossil.
