Question

repetition and replication
a student is writing his procedure for his science fair project. his teacher reminded him that his experiment should include repetition and should be replicable. here is the procedure he came up with to determine which brand of diaper is the most absorbent:

1. purchase 5 different brands of diapers and measure their weight.
2. have baby sister wear each diaper for 1 hour.
3. measure the weight of the diaper after 1 hour to see how much liquid it absorbed.
4. do the experiment again every day for a week.

does the students proposed procedure include repetition? why or why not?
a yes, the experiment includes repetition because the student tests 5 different brands of diapers.
b yes, the experiment includes repetition because the student performs the experiment multiple times.
c no, the experiment does not include repetition because the student only tests the diapers on his sister and not any other babies.
d no, the experiment does not include repetition because the student only has the baby wear the diaper for 1 hour at a time instead of repeating the experiment with different time periods.
is the students experiment replicable?

Explanation:

Repetition in an experiment means conducting the same experiment multiple times. In this case, the student only tests each diaper on his sister once (for 1 hour each). Testing on his sister alone and not repeating the same test (e.g., using the same diaper - brand and baby - tester combination multiple times) means there is no repetition. Options A and B are incorrect as testing different brands (A) or doing the experiment daily (which is replication across days, not repetition of the same test setup) (B) are not true repetition. Option D is incorrect because the time - period aspect is not related to repetition in the sense of repeating the same experimental unit test. Option C is correct as the lack of repeating the same diaper - baby test (just using his sister once for each brand) means no repetition.

Answer:

C. No, the experiment does not include repetition because the student only tests the diapers on his sister and not any other babies.