Final answer:
Electric shocks can cause unpleasant sensations, muscular contractions, disruption of heart electrical patterns, and burns depending on the current flowing through the body.
Step-by-step explanation:
Electric shocks can have different effects on a person depending on the current flowing through their body. For currents less than 5 mA, shocks are typically unpleasant but apparently harmless. At currents between 10 to 20 mA and above, the current can stimulate sustained muscular contractions, causing certain muscles to contract involuntarily. At about 100 to 300 mA, the shock can disrupt the electrical patterns of the heart, leading to a condition called ventricular fibrillation, which can be fatal due to a lack of blood circulation. Currents above 300 mA can also cause burns.