STEPS
1. Label three  bottles.
A – yeast, warm water and sugar
B – yeast, warm water
C – yeast, sugar
2. Put the ingredients in each bottle.
3. Put a balloon over the neck of each bottle.
4. Put the bottles in a warm place and Wait 20 minutes.

RESULTS
1. The balloon on bottle A inflated the most.
2. The balloon on bottle C inflated the least.
3. Yeast needs sugar and water tu carry out nutrition.

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