Answer:
An extraneous variable is eliminated, for example, if background noise that might reduce the audibility of speech is removed as Unknown extraneous variables can be controlled by randomization.
A band in the test line but not a band in the control line indicates an inconclusive pregnancy test.
<h3>What is Pregnancy test?</h3>
This test involves the measurement of Human chorionic gonadotropin in the body as it is synonymous with pregnancy.
A band in the test line but not a band in the control line indicates an inconclusive pregnancy test while a band in the control line but not a band in the test line indicates a negative test result.
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Not necessarily the food chain may change for some animals because they eat that one species
Sorry for the handwriting
Answer:
The types of epithelia are classified by the shapes of cells present and the number of layers of cells
