So i am doing a physics lab about the expansion of water. esentially i have a cork on a glass bottle filled with water. in two holes in the cork i have a pippette and then a go temperature probe to measure the temperature. the water is displaced into the pippette so i can measure the volume of expansion when the water heats up and cools. i first have to cool the water to 0 degrees and then have it in a room temperature room and record every mm expalnsion and the corresponding increase in temperature until 15 degrees. other than not accounting for the increase of expansion of the glass bottle, what other sources of error could there be for this experiment?