The length of a pencil The weight or mass of a pencil Gram The volume of a pencil The weight or mass of a hippopotamus Pounds The length of a hippopotamus The length of a fingernail clipping The weight or mass of a fingernail clipping The volume of a sink The volume of a bowl The length of a chalkboard or whiteboard The weight or mass of a chalkboard or whiteboard The length of the border between the United States and Canada​