A researcher is interested in determining the average length and weight of loblolly pine tree needles in the southeast United States. Will the data be obtained through observation or experimentation?

The correct answer will be - both observation and experimentation

Explanation:

The determination of length and weight of the pine trees of the forest can be determined by the scientific method.

The observation must be done to measure the length and weight of the trees using the instruments whereas the calculation of the measurement must be done through a systematic approach to calculating the average.

Both observation and experimentation are steps of the scientific method which can lead to the answer therefore, both observation and experimentation are correct.