an cracking optional occur in random to be heard
noise is incomprehensibility. library has rules_about_being_quiet efron's_dice is strange_loop. silence_means_there is no_sound. audible_sound_sequence is discontinuous_event_series. if deafen occurs then make_noise occurs. instructions_for_cracking is manual. sound has frequency_and_amplitude if_tap is broken_may_leak. droste_effect is strange_loop.