My father ask me to wash his clothes today.So when i was set to do what i was ask to do ,i took one basin and one iron pail that my dad uses for bath and proceeded to work .Later my mum came and saw me using the pail she began to shout at me asking why i dont have a single regards for something that belong to my father.I then told her mummy see eh if i dont use this pail the marginal utility derived is zero,but as i am using it the marginal utility has increase to 70% and percentage for total utility will be 90%.Now she reported me that i disobeyed her.What have i done wrong?