An apparatus and a method facilitate single user and tournament play of wagering games. Numerical\u2062\u2062Formula\u2062\u20621\u03b1\xd7tr>0. The system further includes a wireless communication network for communicating the acquired product identification information provided by the plurality of portable terminals to a central host facility. A piezoelectric vibrator is supported by the rotating member so as to swing its ultrasonic-wave transmittingreceiving surface about a swing axis that is orthogonal to the central axis. An advantage is also to measure with precision the stroke of the indenter with corresponding control in precision of the penetration of the indenter in the sample material.