(a) No person shall throw, catch, kick or strike any baseball, football, basketball, soccer, golf or tennis ball, or similar object, nor shall any person engage in any sort, game or other competition except in areas designated and maintained therefor. No such use will be allowed at any time if the desired area has previously been allotted by permit issued pursuant to the provisions of these rules.

(b) No person shall engage in any toy or model aviation, kite-flying, model boating or model automobiling except at such times at such places designated or maintained therefore.

(c) No person shall roller skate, roller blade, ski, skateboard, sled or coast on any kind of vehicle except in areas designated and maintained for such use.