2.54 mL of ethanol to mol ethanol (Hint: the density of ethanol is 0.789
g/mL.)

0.04350179862

Explanation:

Make sure to check for sig figs though. Basically, you have 2.54 mL and you multiply that by the 0.789 g/mL and mL cancels out and you are left with 2.00406g. There are 46.06844 grams per mol of ethanol, so to cancel out grams we multiply by 1/46.06844. And then we are left with 0.04350179862 mol

geosphere and hydrosphere.

this is because the geosphere has to do with geological events, while the hydrosphere controls all water on earth.