For ice piece 1, place 2 teaspoons of water into one of the spaces in the ice cube tray. To make ice piece 2, place 2 teaspoons of water into the sealable plastic bag. Carefully squeeze as much of the air out of the bag as possible without spilling any water. Then seal the bag. Place the sealed bag on a flat surface in the freezer. Place the ice cube tray in the freezer at the same time. Leave both in the freezer for four hours. Record the start time and the time when you can remove the ice.