the options in the dropdown box for a) are: about 1.83 hours, about 2.05 hours, about 3.54 hours, and 5.51 hours.
the options in the dropdown box for b) are: about 1 hour, about 1.73 hours, about 3.02 hours, and about 4.75 hours.
the options in the dropdown box for c) are: about 1.56 hours, about 2.82 hours, about 3.64 hours, and about 5.71 hours.