Question: Open a jelly jar that is stuck shut using a rubber band.
Option 0: Place the jar on a table.  Loop the rubber band over your index finger.  Point your index finger at the jar.  Pull back on the band, then release.  Hit the jar with the band until the lid looses.
Option 1: Find a wide rubber band, wrap it around the lid of the jar.  The band allows you to apply more force to the lid. Twist the lid off.
Answer: 1