5 grams will be left. After the first 1000 years, there will be half of 20 left, or 10. After 2000 years, half of 10 will remain, which is 5.
The answer to the blank i think is bond im not 100% sure though..
Nutrient Leaching
Leaching is the process where dissolved nutrients in the
soil profile moves downward with percolating water. It is the loss of
water-soluble plant nutrients from the soil. The nutrients that seep through
the rooting zone may be recycled if roots grow deeper.
DNA strands are split apart to allow an opening for replication. The
opening has two replication forks so synthesis goes toward them in 5' to
3' direction.
Hope This Helps
