Final answer:
When working with a fume hood, your head should be positioned outside of the fume hood to minimize the risk of inhaling harmful fumes and vapors.
Step-by-step explanation:
When working with a fume hood, your head should be positioned outside of the fume hood. The purpose of a fume hood is to protect you from harmful fumes and vapors that may be produced during experiments. By keeping your head outside of the fume hood, you minimize the risk of inhaling these hazardous substances.
It is important to always follow the instructions provided by your teacher or lab supervisor when using the fume hood. Additionally, make sure to tie back any long hair and tuck loose clothing in to prevent them from getting close to the fume hood or any open flames.