Ireturned home late after a tough day at work, but my roommate forced me to do the onerous task of cleaning the kitchen. based on the context, onerous likely means relaxing burdensome enviable

Based on the context, onerous likely means burdensome.

every person should make it a priority to serve at least two hours per week.

it's an extremely important civic responsibility that is invaluable to citizens most in need is the correct one