The Formal Report
The Objective defines the primary goal of that this report summarizes. This objective is usually set by higher authority (such as your supervisor) and may not be the objective you worked under when doing the experimental work. This is because the same set of data may be used to achieve more than one goal.
This must be the specific objective you were assigned by the lab supervisor to answer for this formal report.
This is almost always a single sentence of very simple construction. It is standard practice to exactly copy the objective that you have been assigned into this section. This prevents any confusion about what is expected in the report.