The graph indicates the RATE of absorbtion of carbon dioxide into a body of water. The rate varies with time. Positive quantities mean that the carbon dioxide is being abosrbed into solution, while negative quantities mean the carbon dioxide is being released to the air.
For each interval, enter all letters whose corresponding statements are true for that interval.)
1. The interval from a to b
2. The interval from b to c
3. The interval from c to d
4. The interval from d to e
5. The interval from e to f

A. Carbon dioxide is being absorbed by the water on this interval.
B. Carbon dioxide is being released from the water on this interval.
C. The rate at which the carbon dioxide is being absorbed is increasing on this interval.
D. The rate at which the carbon dioxide is being absorbed is decreasing on this interval.
E. The total amount of carbon dioxide in the water is increasing on this interval.
F. The total amount of carbon dioxide in the water is decreasing on this interval.