Hello mouthshutt.today I tell somethimg about the gate virtual calculator.i compare this calculator to other but this is too slow.its design is too older like 2002 or 2003.it has no new features are installed.i buy it from ebay.when I buy it I am very happy because I thought that this is very usefull.but it is a toy .it is not usefull to anyone.the scientific calculator is best compare to this. so I advise to dont buy this.thankyou.