A small bubble rises from the bottom of a lake, where the temperature and pressure are 8°C and 6.4 atm, to the water's surface, where the temperature is 25°C and pressure is 1.0 atm. Calculate the final volume (in ml) of the bubble if its initial volume was 2.1 ml.
a. 0.070 ml
b. 21 ml
c. 14 ml
d. 42 ml