1. Get a piece of an apple. Another piece for avocado.
2. Slice in two parts. 3. Put the slice of an apple in a container with cover.
4. Put the other slice on a container without any cover and let it stay for a few minutes.
5. Observe what happened to the apple or avocado. Compare the two slices. a. Was there any difference? b. What happened to the uncovered slice of apple or avocado? Why? c. What happened to the covered slice of apple or avocado? Why?

patulong
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