One hundred grams of a certain chemical is removed from its airtight container and
immediately placed in a 20 gram dish on a sensitive scale. The scale reads 120 grams. The
chemical absorbs water from the air at a rate of 15e^-t grams per minute, where t is the
time in minutes that the chemical has been exposed to air.
a) What is the reading on the scale after t minutes?
b) What is the reading on the scale after a very long time has passed?
I am not asking you to do this for me, I just have no idea how to do it an help would be appreciated
Thanks in advance