<prompt> Enye inhlobo yewashi lasendulo lalinesiqu eside esinamamaki ayisihlanu aguquguqukayo kanye ne-crossbar ephakanyisiwe eyayibeka isithunzi kulawo ma-mark. Kwakubekwe ngasempumalanga ekuseni ukuze ilanga eliphumayo libeke isithunzi kulawo ma-mark, futhi laphendukela ngasentshonalanga emini ukuze libambe izithunzi ntambama. Ama-obelisk asebenza ngendlela efanayo: isithunzi esifakwe kumamaki azungeze amaGibhithe sasivumela ukubala isikhathi. I-obelisk nayo yabonisa ukuthi kwakusekuseni noma ntambama, kanye ne-solstices yasehlobo neyasebusika. Iwashi lesithathu lesithunzi, elakhiwa ngo-1500 BC, lalinomumo we-T-square. Lalinomumo we-T-square.  <response>: kungakhathaliseki ukuthi kwakusekuseni noma ntambama 