An engineer is evaluating two HVAC controllers for use in a large project. Each unit was used to control the air temperature in a test chamber that was subjected to external heating to simulate a day $/$ night cycle. The line plot below shows the results for the two units for a twenty $-$ four $-$ hour period, along with the target temperature. Identify any misrepresentation issues in the graph. Select all that apply. State ways in which the graph could be improved. Select all that apply.