Lilian car wont start she is using the scientific method to determine the cause the car wont jumpstart so the battery is not the cause of the problem what should she do next?

Just because the jumpstart did not start the car does not eliminate the battery as suspect. Have the battery tested. If the battery tests good and the car still does not start (assuming the starter is spinning fast enough). the next step is to ensure that fuel is reaching the engine. Following that, the next step is to check the wiring from the ignition switch to the starter solenoid/relay and look for a loose or disconnected wire.