Blood pressure is governed by five elements--the strength of the heartbeat, the volume of blood, the viscosity of the blood, the resistance of the arterioles, and the elasticity of the arterial walls. An abnormality of any of these can cause the blood pressure to be too high or too low.
Depending on the complexity of the case a trial can last anywhere from one day to six months or longer. If you are asking how long a rape prosecution takes you are probably looking at 6 months to a couple of years.
You have been summoned for one day or one trial. Most jury trials last 3- 7 days, but some may go longer. The trial judge will advise you of the length of the trial. If you are assigned to a case, you will be required to serve until the trial is completed. Generally, if you are not selected for a trial, your jury service will be completed in one day. The day that you report for jury service, you may be assigned to more than one courtroom to go through the selection process. Upon completion of your jury duty, you will be exempt from jury service for one year.