---------------------------------------------------------------------------
case 10 : $Cash = 0; break;
case 20 : $Cash = 20; break;
case 30 : $Cash = 40; break;
case 40 : $Cash = 60; break;
case 50 : $Cash = 80; break;
case 100 : $Cash = 200; break;
case 200 : $Cash = 500; break;
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Não seria 10?